Outer hub assembly and spindle motor including the same in hard disk drive and method for servo-track writing

• US 7,474,501 B2
• Filed: 06/23/2005
• Issued: 01/06/2009
• Est. Priority Date: 06/29/2004
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Oh, Dong-ho, Han, Jae-hyuk, Byun, Yong-kyu, Koo, Ja-choon
• Primary Examiner(s): KLIMOWICZ, WILLIAM JOSEPH
• Application Number:
  US11/159,215
• Publication Number:
  US 20050286164A1
• Time in Patent Office: 1,293 Days
• Field of Search: 360/98.08, 360/98.07, 360/99.04, 360/99.05, 360/99.08, 360/99.12
• US Class Current: 360/98.07
• CPC Class Codes: G11B 17/038 Centering or locking of a plurality of discs in a single cartridge
• CPC Class Codes: G11B 25/043 using rotating discs

Abstract

A spindle motor, which rotates a plurality of data storage disks in a hard disk drive, the spindle motor including: a shaft; an inner hub rotatably installed on an outer periphery of the shaft; and a hub assembly, which includes: an outer hub detachably coupled to an outer periphery of the inner hub, the outer hub shaped such that a plurality of disks and at least one spacer for maintaining an interval between adjacent disks of the plurality of disks can be secured to an outer periphery of the outer hub; and a fastening member coupled to a top portion of the outer hub and fixing the outer hub to the inner hub. The outer hub assembly to which the plurality of disks are secured can be mounted on an off-line servo-track writer, and can also be attached as is to the spindle motor after servo-track writing is completed.

Claims

1. A hub assembly comprising:

an outer hub;

a fastening member coupled to a top portion of the outer hub; and

an inner hub or a motor shaft;

wherein said outer hub is detachably coupled to an outer periphery of the inner hub or to an outer periphery of the motor shaft, the outer hub is shaped such that a plurality of disks and at least one spacer for maintaining an interval between adjacent disks among the plurality of disks are fitted to an outer periphery of the outer hub;

wherein said fastening member fixes the outer hub to the inner hub or the motor shaft;

wherein the outer hub comprises a cylindrical body unit, a support unit disposed on a bottom portion of the body unit and supporting the plurality of disks, and a clamping unit disposed on a top portion of the body unit and clamping the plurality of disks; and

wherein the body unit comprises an upper body and a lower body, the clamping unit is integrated with a top portion of the upper body in the form of a flange, and the support unit is integrated with a bottom portion of the lower body in the form of a flange;

wherein the clamping unit and the top portion of the upper body are parts of a first single-piece unit, and the support unit and the bottom portion of the lower body are parts of a second single-piece unit.

2. The hub assembly of claim 1, wherein the inner hub is the inner hub of a spindle motor in a hard disk drive and the motor shaft is the motor shaft of an off-line servo-track writer.

3. The hub assembly of claim 2, wherein the fastening member is fixed to the inner hub or the motor shaft using a fastening screw that is fastened to a shaft of the spindle motor or to the motor shaft of the off-line servo-track writer.

4. The hub assembly of claim 2, wherein the fastening member is fixed to the inner hub using a plurality of fixing screws that are fastened to the inner hub of the spindle motor, or fixed to the motor shaft using a fastening screw that is fastened to the motor shaft of the off-line servo-track writer.

5. The hub assembly of claim 2, wherein a plurality of outer hub assemblies are mounted on the motor shaft of the off-line servo-track writer.

6. The hub assembly of claim 5, wherein the motor shaft comprises a larger diameter portion and a smaller diameter portion, the larger diameter portion is inserted into an outer hub of one of the plurality of outer hub assemblies, and the smaller diameter portion is inserted into an outer hub of at least another one of the plurality of outer hub assemblies.

7. The hub assembly of claim 6, wherein a coupling member is interposed between adjacent outer hub assemblies of the plurality of outer hub assemblies, and the coupling member is fitted to an outer periphery of the smaller diameter portion of the motor shaft.

8. The hub assembly of claim 7, wherein the coupling member comprises a hub insertion unit inserted into an outer hub of one of the plurality of outer hub assemblies, and a groove insertion unit formed on one surface of the hub insertion unit to be inserted into a groove formed on a top surface of an outer hub of another one of the plurality of outer hub assemblies.

9. The hub assembly of claim 5, further comprising a plurality of pressure members installed on the motor shaft to correspond to the plurality of outer hub assemblies such that the plurality of pressure members can get into and out of the motor shaft,

wherein the motor shaft has a cylindrical shape with a predetermined diameter.

10. The hub assembly of claim 9, wherein the plurality of pressure members are projected outwardly from an outer peripheral surface of the motor shaft and forced onto inner peripheral surfaces of the outer hub assemblies by pressure.

11. The hub assembly of claim 9, further comprising at least one projection installed on the motor shaft so that the projection can get into and out of the motor shaft,

wherein the at least one projection is inserted into a slot formed on a top surface of an outer hub of a corresponding outer hub assembly.

12. The hub assembly of claim 9, wherein a coupling member is interposed between adjacent outer hub assemblies of the plurality of outer hub assemblies and fitted to the outer periphery of the motor shaft.

13. The hub assembly of claim 1, wherein a bottom portion of the upper body and a top portion of the lower body have screw portions such that the screw portions can mesh with each other.

14. The hub assembly of claim 1, wherein the clamping unit is integrated with the top portion of the body unit in the form of a flange, and the support unit is a separate ring-shaped member coupled to the bottom portion of the body unit.

15. The hub assembly of claim 14, wherein an inner surface of the support unit and the bottom portion of the body unit have screw portions such that the screw portions can mesh with each other.

16. The hub assembly of claim 1, wherein the clamping unit is a separate ring-shaped member coupled to the top portion of the body unit, and the support unit is integrated with a bottom portion of the support unit in the form of a flange.

17. The hub assembly of claim 16, wherein an inner surface of the clamping unit and the top portion of the body unit have screw portions such that the screw portions can mesh with each other.

18. The hub assembly of claim 1, wherein a clamping washer is interposed between the clamping unit and an uppermost disk among the plurality of disks to apply an elastic force to the plurality of disks.

19. The hub assembly of claim 1, wherein a groove into which the fastening member is inserted is formed on a top surface of the outer hub, at least one projection is formed on an outer peripheral surface of the fastening member, and at least one slot into which the projection is inserted is formed on an inner peripheral surface of the groove.

20. The hub assembly of claim 1, wherein a groove into which the fastening member is inserted is formed on a top surface of the outer hub, and the fastening member inserted into the groove is screwed to the outer hub using a plurality of coupling screws.

21. The hub assembly of claim 1, wherein the first and the second single piece units are each of a unitary construction.

22. A spindle motor, which rotates a plurality of data storage disks in a hard disk drive, the spindle motor comprising:

a shaft;

an inner hub rotatably installed on an outer periphery of the shaft; and

a hub assembly comprising;

an outer hub detachably coupled to an outer periphery of the inner hub, the outer hub shaped such that the plurality of disks and at least one spacer for maintaining an interval between adjacent disks of the plurality of disks can be secured to an outer periphery of the outer hub; and

a fastening member coupled to a top portion of the outer hub and fixing the outer hub to the inner hub,

wherein the hub assembly can be separated from the spindle motor to be mounted on an off-line servo-track writer;

wherein the outer hub comprises a cylindrical body unit, a support unit disposed on a bottom portion of the body unit and supporting the plurality of disks, and a clamping unit disposed on a top portion of the body unit and clamping the plurality of disks;

wherein the body unit comprises an upper body and a lower body, the clamping unit is integrated with a top portion of the upper body in the form of a flange, and the support unit is integrated with a bottom portion of the lower body;

wherein the clamping unit and the top portion of the upper body are parts of a first single-piece unit, and the support unit and the bottom portion of the lower body are parts of a second single-piece unit.

23. The spindle motor of claim 22, wherein a bottom portion of the upper body and a top portion of the lower body have screw portions such that the screw portions can mesh with each other.

24. The spindle motor of claim 22, wherein the clamping unit is integrated with the top portion of the body unit in the form of a flange, and the support unit is a separate ring-shaped member coupled to the bottom portion of the body unit.

25. The spindle motor of claim 22, wherein an inner peripheral surface of the support unit and the bottom portion of the body unit have screw portions such that the screw portions can mesh with each other.

26. The spindle motor of claim 22, wherein the clamping unit is a separate ring-shaped member coupled to the top portion of the body unit, and the support unit is integrated with the bottom portion of the body unit in the form of a flange.

27. The spindle motor of claim 26, wherein an inner peripheral surface of the clamping unit and the top portion of the body unit have screw portions such that the screw portions can mesh with each other.

28. The spindle motor of claim 22, wherein a clamping washer is interposed between the clamping unit and an uppermost disk of the plurality of disks to apply an elastic force to the plurality of disks.

29. The spindle motor of claim 22, wherein a groove into which the fastening member is inserted is formed on a top surface of the outer hub, at least one projection is formed on an outer peripheral surface of the fastening member, and at least one slot into which the projection is inserted is formed on an inner peripheral surface of the groove.

30. The spindle motor of claim 22, wherein a groove into which the fastening member is inserted is formed on a top surface of the outer hub, and the fastening member inserted into the groove is screwed to the outer hub using a plurality of coupling screws.

31. The spindle motor of claim 22, wherein the fastening member is fixed to the inner hub using a fastening screw that is fastened to the shaft of the spindle motor.

32. The spindle motor of claim 22, wherein the fastening member is fixed to the inner hub using a plurality of fixing screws that are fastened to the inner hub of the spindle motor.