KR100786615B1 - Spindle motor for hdd improved on processing construction of sleeve and groove of hub - Google Patents

Abstract

A spindle motor for a hard disc drive with an improved machining structure of grooves for a sleeve and a hub is provided to improve reliability while securing a large oil keeping space by the grooves substituted for conventional thrust bearing. A spindle motor for a hard disc drive with an improved machining structure of grooves for a sleeve and a hub includes a stopper(40). The stopper of a predetermined diameter is fitted to a lower part of the sleeve(50) and supports a shaft(30) fitted thereto. The sleeve has a flange(100) projected on the top of the sleeve, which is connected to a hub(10) vertically. A first groove(821) is formed at the upper surface of the sleeve to generate axial dynamic pressure. The hub is has a flange(110) having an inner diameter corresponding to the outer diameter of the sleeve to insert a part of the upper end of the sleeve, and has a groove(120) recessed to correspond to the flange of the sleeve. A second groove(822) is formed on the surface of the center portion of the hub except for the flange and the groove to generate axial dynamic pressure. A part of the center portion of a base(60), which corresponds to the flange of the hub, is recessed in the hub combining direction.

Description

SPINDLE MOTOR FOR HDD IMPROVED ON PROCESSING CONSTRUCTION OF SLEEVE AND GROOVE OF HUB}

1 is a view for briefly explaining the structure of a typical hard disk drive.

Figure 2 is a view for briefly explaining the structure of a conventional spindle motor for a hard disk drive.

3 is a view for conceptually explaining the structure of a spindle motor for a hard disk drive according to the present invention.

4 is a view for explaining the dynamic pressure generation of the spindle motor for a hard disk drive according to the present invention.

5 is a view for explaining a sleeve of the spindle motor for a hard disk drive according to the present invention.

Figure 6 is a view for explaining a hub of the spindle motor for a hard disk drive according to the present invention.

*** Brief description of the reference numerals for the main parts of the drawings ***

1: platter 2: spindle motor

3: head 4: head arm

5: sppping motor

10: HUB 20: MAGNET

30: shaft 40: thrust bearing

50: SLEEVE 60: Base

70: stator core 80: groove (GROOVE)

90: thrust plate 100: coupling jaw

110: restraint jaw 120: coupling groove

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle motor that provides rotational force to a plurality of platters in a hard disk drive (HDD), and more particularly to a machining structure of a groove for generating dynamic pressure in the spindle motor.

In general, a hard disk drive refers to an auxiliary memory device that stores and reads data while rotating a magnetic aluminum plated aluminum substrate. However, a hard disk drive cannot be used interchangeably with another, but it is inexpensive. Due to its large memory capacity, it is widely used in small computers. In particular, a small hard disk drive is used in a personal computer (PC) because it is suitable for use in a personal computer. The capacity of the hard disk drive used in such a personal computer was basically 1GB level in the mid-1990s, and more than 16GB was generalized in the late 1990s. Globally, storage capacity is growing at 60% per year, with prices falling 12% per quarter.

Usually, the hard disk drive has a platter shaped like a record plate, and a concentric circle called a track is drawn thereon to record data electronically in the concentric circle. As shown in FIG. (1) consists of a stacked hard disk, spindle motor (2), head (3), head arm (4) and stepping motor (5).

The platter (1) is a thin coating of magnetic magnetic material on a metal disc, and due to the limitation of the capacity that can be recorded on one sheet, a high capacity hard disk uses several platters (1) depending on the size and number of hard disks. The size of is determined.

The spindle motor 2 rotates at a constant speed (for example, 3600rpm, 5400rpm, 7200rpm) when power is supplied to a motor that rotates the platter 1, and at least one platter 1 is provided on the spindle axis. It is designed to rotate at the same time. Controlling the exact rotation rate of the spindle motor 2 is of paramount importance for reliable reading and writing of data.

The head 3 also moves horizontally above and below the rotating platter 1 to read and write data to the platter 1.

In addition, the head arm 4 is an arm that allows the head 3 to move and adjusts the position of the head 3 under the command of the controller chip.

Finally, the stepping motor 5 is a driving force for moving the head 3 to the position of the platter 1, and the performance of the motor is good or bad. Total time spent for transmission) is determined.

In particular, the spindle motor in the field to which the present invention is applied belongs to a brushless-DC motor and transmits a rotational force to the center of the platter which is the disc of the disk to rotate the platter. In addition to the hard disk drive, the main motor is widely used as a laser beam scanner motor for a laser printer, a motor for a floppy disk drive (FDD), and an optical disk drive motor such as a compact disk (CD) or a digital versatile disk (DVD). do.

In addition, recently, in a machine that requires a large capacity and high speed driving force such as the hard disk drive, in order to minimize noise and non-repetitive run out (NRRO), a fluid having a lower driving load (or driving friction) than a conventional ball bearing type is required. The trend is to use spindle motors with dynamic bearings.

Here, the hydrodynamic bearing is basically a thin oil film formed between the rotating body and the fixed body to support the rotating body with the pressure generated during rotation, so that the friction load is reduced because the rotating body and the fixed body do not contact each other. Therefore, the fluid dynamic bearing spindle motor (Fluid Dynamic Bearing Spindle Motor) is applied to maintain the shaft of the motor that rotates the disk only the lubricating oil (dynamic pressure: pressure returned to the center driven by the centrifugal force of the rotating shaft) This is distinguished from the ball bearing spindle motor which supports the shaft with steel balls.

In addition, in the case of the spindle motor to which the ball bearing is applied, noise and vibration (NRRO) are generated due to friction between the ball bearing and the shaft, and in particular, the vibration acts as an obstacle to increasing the track density of the hard disk. The hydrodynamic bearing has no metal friction on the basis of centrifugal force, and as the rotation speed increases, a sense of stability is increased, and thus, the hydrodynamic bearing is preferentially employed in a hard disk drive due to its low noise and vibration characteristics.

As such, the internal structure of the conventional spindle motor to which the hydrodynamic bearing is applied has a base 60, a sleeve 50, a coil wound stator core 70, a shaft 30, and a hub as shown in FIG. 10 and the magnet 20.

The spindle motor is fixed to the sleeve 50 is vertically coupled to the inner side of the base 60 to form an appearance, the coil stator core 70 is wound around the upper side of the base 60 is mounted and the The shaft 30 is rotatably inserted through the inner center. And the lower end of the shaft 30 is coupled to the disk-shaped thrust bearing 40 rotatably coupled with the shaft 30 and its lower end is shielded from the outside by a cover plate, the upper end of the shaft 30 is internal The cap-shaped hub 10 opened downward is coupled. In addition, a magnet 20 is attached to a position facing the stator core 70 at an inner end of the hub 10, and an oil gap is formed between the outer circumferential surface of the shaft 30 and the thrust bearing 40 and the sleeve 50. The oil gap is filled with a fluid such as lubricating oil or grease.

Accordingly, the hydrodynamic bearing spindle motor having the above structure has a hub 10 and a shaft coupled thereto by an electromagnetic repulsive force applied between the stator core 70 and the magnet 20 in which the coil is wound when an external power is applied. 30 rotates.

In addition, in the inner circumferential surface of the sleeve 50, a plurality of grooves 80 are formed in the shape of a herringbone or spiral, and when the shaft 30 rotates, the oil filled in the oil gap is pressurized. By moving to the center of the groove 90 by the gradient to generate the fluid dynamic pressure to support the shaft 30, to prevent the fluid filled in the oil gap scattering.

However, the conventional spindle motor illustrated in FIG. 2 has a structure in which the thruster bearing 40 is at the bottom, and the sleeve 50 and the hub 10 as anti-friction measures of the upper sleeve 50 surface and the hub 10. ) MoS2 coating must be applied and the process is added by MoS2 coating.In addition, the reliability test (50,000 hours at 80 ℃) causes a problem due to the small amount of oil, and the size (circumference size) of the thrust bearing 90 is increased. It is small and the size of the groove 80 is limited, so that the dynamic pressure in the axial direction becomes small.

In addition, in order to maintain the flying height, the thrust bearing 90 has upper and lower clearances. To this end, the assembly precision of the shaft 30 and the thrust bearing 40 is less than or equal to 1 μm. The groove shape should be different to satisfy the characteristics of the Fpc up-down direction, which is one of the reliability tests, and when the thrust bearing 40 and the shaft 30 are assembled, the direction is matched to the groove direction. Difficulties arise in assembling.

Accordingly, the present invention has been made in view of the above problems, and in order to increase the dynamic pressure in the axial direction, a groove is directly processed on the hub and the sleeve surface without using a thrust bearing, so that the dynamic pressure characteristic in the axial direction is obtained. The object of the present invention is to provide a spindle motor for a hard disk drive that can improve the performance of the disk drive.

In addition, it is another object to provide a spindle motor for a hard disk drive, which is excellent in reliability while maintaining a large oil holding space.

In addition, when assembling the spindle motor, there is no need to check the directionality of the groove due to the thrust bearing, and it is possible to provide a spindle motor for a hard disk drive that can improve the assemblability of the spindle motor by easily assembling the shaft at right angles. There is another purpose.

In order to achieve the above object, the spindle motor for a hard disk drive having an improved groove processing structure of the sleeve and the hub of the present invention has a hub 10 in which a magnet 20 is installed on the inner side in a downwardly open cap shape, the hub One side is coupled to the center of the shaft 30, the shaft 30 is coupled to the shaft 30 having an oil gap so that the shaft 30 is rotatable, radial radial dynamic pressure for generating a dynamic pressure on the inner peripheral surface A stator core wound around a coil 50 coupled to the base 60 so as to face the sleeve 50 in which the grooves 81 are formed at a predetermined position, the base 60 fixing the sleeve 50, and the magnet 20. (70) A spindle motor for a hard disk drive comprising a thrust plate (90) for closing one side of the sleeve (50), which is inserted into and fixed to a lower portion of the sleeve (50) and has a predetermined inner diameter. An end of the shaft 30 is inserted into an inner circumferential surface thereof, and further includes a stopper 40 that supports the shaft 30 and prevents detachment. The sleeve 50 has an upper surface vertically coupled to the hub 10. Protruding the engaging jaw (100) having a predetermined size to the outside of the, and forming an axial dynamic pressure generated first groove (821) in the upper surface, the hub (10) of the sleeve (50) The restraint jaw 110 is formed to protrude with an inner diameter corresponding to the outer diameter of the sleeve 50 so that a part of the upper end can be inserted, and the inside thereof corresponds to the engaging jaw 100 of the sleeve 50. The coupling groove 120 is recessed to form an axial dynamic pressure generating second groove 822 on the center side surface except the restraining jaw 110 and the coupling groove 120, and the base ( 60, a portion corresponding to the restraining jaw 110 of the hub 10 in a direction perpendicular to the hub 10 toward the center side of the hub 10. It is characterized by forming a recessed inwardly.

At this time, the axial dynamic pressure generating second groove 822 formed on the central side surface of the hub 10 is processed in the form of a herring-bone, and the engaging jaw 100 of the sleeve 50 is formed. Axial direction dynamic pressure generating first groove 821 formed in the) is characterized in that it is processed in the form of a spiral (Spiral).

In addition, the restraint jaw 110 of the hub 10 is obliquely processed in a direction in which the end thereof faces the sleeve 50, and the base 60 is perpendicular to the restraint jaw 110 of the hub 10. The end portion is diagonally processed in a direction facing the hub 10 toward the center, which is a coupling site, to prevent oil from scattering.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification. In addition, when a part is said to "include" a certain component, which means that it may further include other components, except to exclude other components unless otherwise stated.

Now, a spindle motor for a hard disk drive according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. The following terms are defined in consideration of functions in the present invention, and are intended to be used by users, operators, or customs. It may vary. Therefore, the definition should be made based on the contents throughout the present specification.

3 is a view for conceptually explaining the structure of a spindle motor for a hard disk according to the present invention, Figure 4 is a view for explaining the dynamic pressure generation of the spindle motor for a hard disk drive according to the present invention. As shown in FIG. 3, the spindle motor for a hard disk drive of the present invention includes a rotating part consisting of a hub 10, a magnet 20, and a shaft 30, a sleeve 50, a base 60, and a stator core 70. And it is composed of a fixing portion consisting of a thrust plate (90). That is, the hub 10 coupled to the shaft 30 is vertically coupled to the base 60 is rotated to the center side.

To describe the configuration of the spindle motor according to the present invention in more detail,

First, the rotating part has a hub shape in which the magnet 20 is installed on the inner side in a cap shape which is downwardly opened, and a shaft 30 having one side coupled to the center of the hub 10.

On the other hand, the fixing portion has an oil gap so that the shaft 30 is rotatable, coupled to the shaft 30 and one side is closed by the thrust plate, the radial direction dynamic pressure to generate a dynamic pressure on the inner surface A sleeve 50 having a groove 81 formed at a predetermined position, a base 60 for fixing the sleeve 50, and a coil coupled to the base 60 to face the magnet 20 so as to face the stator core 70. ).

Here, the spindle motor according to the present invention does not have a thrust bearing used in the conventional spindle motor, the shaft on the upper surface of the sleeve 50 and the lower surface of the hub 10 coupled vertically with the shaft 30 A first groove 821 and a second groove 822 for directional dynamic pressure generation are formed to float the hub 10 and support the shaft 30.

Accordingly, the spindle motor according to the present invention processes the grooves directly on the surfaces of the hub 10 and the sleeve 50 facing each other without using a thrust bearing to increase the dynamic pressure in the axial direction. The dynamic pressure in the direction of ()) is greatly improved, and oil holding space is largely secured in the space occupied by the conventional thrust bearing, so that problems caused by oil can be improved even in the reliability test.

Referring to the operation structure of the spindle motor according to the present invention, the spindle motor for a hard disk drive according to the present invention by coupling the magnet 20 to the inner surface of the hub 10 of the cap-shaped downward opening, to the base 60 The hub 10 is rotated by the electric repulsive force formed by the current and voltage applied to the stator core 70 wound by the coupled coil. At this time, by using the hydrodynamic bearing as a bearing means for smooth and stable rotation of the hub 10, the noise and vibration as well as the friction and resistance of the object during the rotational movement significantly reduced.

At this time, the shaft 30, the sleeve 50, the hub 10 and the base 60 constituting the hydrodynamic bearing has a structure as shown in FIG.

The shaft 30 is integrally coupled to one side of the hub 10 by being vertically inserted into and coupled to the inside of the sleeve 50 to form an oil gap, which is a space into which oil is injected.

By the oil filled in the oil gap, the rotating shaft rotates together with the hub 10 in the sleeve 50 coupled to the base 60. At this time, grooves 81 for generating dynamic pressure in the radial direction of the rotating shaft are respectively formed at upper and lower ends of the inner circumferential surface of the sleeve 50.

Meanwhile, the hub 10 according to the present invention has an inner diameter corresponding to the outer diameter of the sleeve 50 so as to vertically insert the upper portion of the sleeve 50 and protrudes to surround the upper portion of the sleeve 50. The confining jaw 110 is formed and the inner side of the confining jaw 110 to form a coupling groove 120 in which a portion is recessed inwards, and together with the coupling groove 120 of the hub 10 The upper side structure of the sleeve 50 has also changed. The thrust bearing of the conventional spindle motor supports the shaft 30 coupled with the hub 10 and prevents the separation and functions for the stable rotation of the rotating part. However, in the present invention, the thrust bearing is removed from the configuration. The structure of the hub 10 and the sleeve 50 was changed to have. In addition, in order to prevent the dynamic pressure in the axial direction from being weakened due to the deletion of the conventional thrust bearings, a herring-bone groove or a spiral pattern is formed at a portion where the hub 10 and the sleeve 50 are in contact with each other. (Spiral) Groove is formed.

Therefore, since the thrust bearing is eliminated, the oil retention space is improved, and the dynamic pressure characteristic in the axial direction of the thrust bearing is preserved as it is.

In addition, another feature of the present invention was the assembly direction by the grooves processed in the thrust bearing of the conventional spindle motor, but since the thrust bearing is eliminated, it is possible to solve the difficulty of assembling directionally when assembling to improve the assemblability. The effect of will occur.

Looking at the present invention in more detail, the hub 10 has a downwardly open cap shape, the magnet 20 for providing an electric repulsive force is installed inside the vertical wall surface, the upper and lower sides are opened and the predetermined inner diameter A cylindrical sleeve 50 having a fixed shape is installed, and the shaft 30, which is a rotating shaft, is rotatably mounted on an inner diameter portion of the sleeve 50.

In addition, the sleeve 50 corresponds to the coupling groove 120 of the hub 10 to form a coupling jaw 100 of a predetermined size on the upper surface vertically coupled to the hub 10 and to be coupled thereto. It is coupled vertically with the hub 10.

At this time, the sleeve 50 has an axial dynamic pressure generating first groove 821 having a spiral pattern on the surface corresponding to the coupling jaw 100, the hub 10 is An axial dynamic pressure generating second groove 822 having a herring-bone shape is formed on the lower surface, which will be described later with reference to FIGS. 5 to 6.

On the other hand, the base 60 is formed by recessing a portion corresponding to the restraining jaw 110 of the hub 10 in the direction perpendicular to the hub 10 to the center side to insert the hub 10 inwards. And, to help the stable rotation of the hub (10).

In addition, the spindle motor according to the present invention is inserted into and fixed to the lower portion of the sleeve 50, has a predetermined inner diameter and the end of the shaft 30 is inserted into the inner circumferential surface to support the shaft 30 and to be separated By further configuring the stopper 40 to prevent the conventional thrust bearing to replace the role of restraining the shaft.

 At this time, as shown in FIGS. 3 to 4, the restraining jaw 110 and the base 60 of the hub 10 according to the present invention are processed in a diagonal direction to a portion in contact with the outer circumferential surface of the sleeve 50, and the sleeve Thrust plate 90 which closes the open one side of the (50) is also the end is bent (Bending) inwards, which is to prevent the oil from flying outwards in the rotation of the rotating part of the cross section is oblique In the direction.

In addition, the oblique machining is to increase the surface tension than when machining in a conventional plane, the oil flowing out of the inner diameter of the sleeve 50, the spindle 10 when the spindle motor is not rotated in the obliquely processed hub (10) In the restrained jaw 110 of the) to form a thin oil film due to the increase in the surface tension is prevented.

Similarly to the restraining jaw 110 of the hub 10, the base 60 may also form an oil film at the diagonally processed portion to prevent the oil from flowing out.

On the other hand, Figure 4 is a view showing a cross-sectional view of the spindle motor according to the present invention for explaining the generation of dynamic pressure.

The sleeve 50 is to insert the shaft 30 therein, in this case, to have an oil gap of a certain space, to fill the oil and to perform the role of the hydrodynamic bearing.

In addition, the sleeve 50 forms a predetermined groove 81 on its inner circumferential surface, and the hub 10 and the shaft 30 are rotated by being formed in the form of a herring-bone or a spiral pattern. When the oil filled in the oil gap is moved toward the center of the groove 81 by the pressure groove, the fluid dynamic pressure is generated to support the shaft 30 in the radial direction. In addition, the groove 81 formed on the inner circumferential surface of the sleeve 30 also serves to prevent scattering of the fluid filled in the oil gap when the hub 10 and the shaft 30 rotate.

Here, the structure of the spindle motor according to the present invention eliminates the conventionally used thrust bearing from the configuration, thereby reducing the processing area of the radial directional dynamic pressure generating groove 81 processed on the inner surface of the sleeve 50 than before. As it can be secured more, the dynamic pressure in the radial direction is further increased to stably support the shaft, thereby finally improving the stable characteristics of the product.

In this case, the spindle motor according to the present invention further removes the thrust plate 90 that opens and closes one side of the stopper 40 or the sleeve 50 that fixes the shaft 30, thereby generating radial directional dynamic pressure. It is a feature that the machining area of the groove 81 can be further secured.

As shown in FIG. 4, when the hub 10 rotates, the shaft 30 integrally coupled with the hub 10 rotates. Grooves 81, 821, 822 formed on the inner circumferential surface and the upper surface of the sleeve 50 supporting the hub 10 and the shaft 30 and the lower surface of the hub by the rotation of the hub 10 and the shaft 30. Fluid dynamic pressure is generated.

As shown in the enlarged drawing, radial directional dynamic pressure F1 is generated by radial directional dynamic pressure generating grooves 81 formed on upper and lower sides of the inner circumferential surface of the sleeve 50 in contact with the shaft 30. This provides a force for supporting the shaft 30 in the radial direction.

In addition, by the axial dynamic pressure generating first groove 821 formed on the upper surface of the sleeve 50 and the axial dynamic pressure generating second groove 822 formed on the lower surface of the hub 10. Dynamic pressure F2 occurs in the axial direction, which raises the hub 10 associated with the shaft 30 while providing a force for supporting the hub 10 in the axial direction.

At this time, the upper surface of the sleeve 50 which is vertically coupled to the hub 10 forms a coupling jaw 100 protruding a predetermined size outward, and recessed in the lower surface of the hub 10 to have a corresponding structure. By forming the coupling groove 120 is vertically coupled, the shaft 10 is coupled to the shaft 30 to rotate together to enable a stable rotation when rotating.

5 is a view for explaining the sleeve of the spindle motor for a hard disk drive according to the present invention, Figure 6 is a view for explaining the hub of the spindle motor for a hard disk drive according to the present invention of the grooves (821, 822) In order to explain the processing structure in detail, a perspective view showing one side cross-section of the sleeve 50 and the hub 10 is shown.

As shown in FIG. 5, the sleeve 50 is cylindrical in shape and has a predetermined inner diameter so that the shaft can be inserted with an oil gap therein.

In addition, radial direction dynamic pressure generating grooves 81 are respectively formed on the inner circumferential surface of the sleeve 50, that is, on the upper and lower sides of the inner circumferential surface of the sleeve 50, in which the shaft is inserted and in contact with each other.

In this case, the radial directional dynamic pressure generating groove 81 is not limited to the shape shown in the drawings, but may be processed into a herring-bone shape or a spiral shape, and Machining structure can also secure the machining area by eliminating thrust bearings.

The sleeve 50 protrudes to form a coupling jaw 100 having a predetermined size to the outside of the upper surface vertically coupled with the hub 10, the coupling jaw 100 is coupled to the hub 10 when the hub 10 It will be coupled to correspond to the coupling groove 120 of the.

On the other hand, the thrust bearing provided in the conventional spindle motor has been deleted in the present invention, so as to increase the dynamic pressure in the axial direction (Axial) without using the thrust bearing, as shown in the drawing coupling jaw 100 of the sleeve 50 Axial direction dynamic pressure generating first groove 821 having a spiral shape is formed on an upper surface of the upper surface, that is, the uppermost surface of the sleeve 50.

In addition, along with the first axial dynamic pressure generating first groove 821 formed on the engaging jaw 100 of the sleeve 50, the dynamic pressure in the axial direction is further increased and the hub ( Axial directional dynamic pressure generating second grooves 822 having a herring-bone shape are formed on the lower surface of the center side.

The hub 10 is to form a restraining jaw 110 to protrude with an inner diameter corresponding to the outer diameter of the sleeve 50 to insert a portion of the upper end of the sleeve 50, the restraining jaw 110 The sleeve 50 is inserted into the inner peripheral surface of the.

At this time, the inner side of the hub 10 to form a coupling groove 120 recessed in a position corresponding to the coupling jaw 100 of the sleeve 50, the restraint jaw 110 and the coupling groove 120 Axial directional dynamic pressure generating second groove 822 is formed on the central side surface except for ().

Therefore, the present invention described above has been described in detail only with respect to the specific examples described, but it is apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications belong to the appended claims. It is natural.

The spindle motor for a hard disk drive having an improved groove processing structure of the sleeve and hub of the present invention having the configuration as described above does not use a thrust bearing for increasing dynamic pressure in the axial direction, and is provided on the lower side of the hub. Herring-bone grooves and spiral-shaped grooves can be directly formed on the upper side of the sleeve to achieve greater dynamic pressure characteristics in the axial direction, thereby providing a greater space for oil retention. While taking large, there is an effect to satisfy the reliability test by improving the problem caused by the oil in the reliability test.

In addition, since the thrust bearing is eliminated, the processing area of radial direction dynamic pressure generating grooves processed on the inner side of the sleeve can be further secured, and the dynamic pressure in the radial direction is further increased to stably support the shaft. It has the effect of improving the stable characteristics of the product.

In addition, the need to directionally assemble in accordance with the processing direction of the groove formed in the conventional thrust bearing is eliminated, and the shaft is easily perpendicular to the shaft by a stopper fixing the shaft and the engaging groove formed in the hub and the shaft during the assembly process of the product. Since it can be assembled, the assembly accuracy, as well as the assembly method and the effect of improving the assembly occurs.

Claims (3)

Hub 10 is provided with a magnet 20 on the inner side in the form of a cap open downward, the shaft 30 is coupled to one side to the center of the hub 10, the oil gap so that the shaft 30 is rotatable A sleeve 50 having a radial direction dynamic pressure generating groove 81 formed at a predetermined position to be coupled to the shaft 30 and generating dynamic pressure on an inner circumferential surface thereof, and a base 60 for fixing the sleeve 50. ), A spindle motor for a hard disk drive comprising a stator core (70) wound around a coil (20) coupled to the base (60) to face the magnet (20), and a thrust plate (90) for closing one side of the sleeve (50). To Inserted and fixed to the lower portion of the sleeve 50 and has a predetermined inner diameter and the end of the shaft 30 is inserted into the inner circumferential surface to support the shaft 30 further includes a stopper (40) to prevent separation , The sleeve 50 protrudes the engaging jaw 100 having a predetermined size to the outside of the upper surface vertically coupled with the hub 10, and the first groove 821 generates axial dynamic pressure to the upper surface thereof. ), The hub 10 has a confining jaw 110 to protrude with an inner diameter corresponding to the outer diameter of the sleeve 50 so as to insert a portion of the upper end of the sleeve 50, and the sleeve ( Forming a coupling groove 120 recessed inward to correspond to the coupling jaw 100 of the 50, the axial dynamic pressure generating agent on the center side except for the restraint jaw 110 and the coupling groove 120 Form two grooves 822, Hard disk drive, characterized in that the center side of the base 60 to form a recess inwardly the portion corresponding to the restrained jaw 110 of the hub 10 in the vertical coupling direction with the hub (10); Spindle motor. The method of claim 1, Axial direction dynamic pressure generating second groove 822 formed on the central side surface of the hub 10 is processed in the form of a herring-bone, the coupling jaw 100 of the sleeve 50 The axial dynamic pressure generating first groove (821) to be formed is processed in the form of a spiral (Spiral); spindle motor for a hard disk drive. The method of claim 1, The restraint jaw 110 of the hub 10 is diagonally processed in a direction in which the end thereof faces the sleeve 50, and the base 60 is a portion that vertically engages with the restraint jaw 110 of the hub 10. A spindle motor for a hard disk drive, characterized in that the end is diagonally processed toward the hub toward the hub to prevent oil from scattering.

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