Apparatus and method for writing servo patterns on a computer hard disk

• US 6,522,494 B1
• Filed: 09/30/1999
• Issued: 02/18/2003
• Est. Priority Date: 09/30/1999
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Magee, David P.
• Primary Examiner(s): Hudspeth, David
• Assistant Examiner(s): WONG, KIN C
• Application Number:
  US09/409,628
• Time in Patent Office: 1,237 Days
• Field of Search: 360/75, 360/51, 360/77.06, 360/78.12, 360/78.05, 360/294.3, 360/294.6, 360/246.6, 360/77.03
• US Class Current: 360/75
• CPC Class Codes: G11B 5/59633 Servo formatting G11B5/59627, G11B5/59677, G11B5/59683, G11B5/59688 take precedence
• CPC Class Codes: G11B 5/59638 Servo formatting apparatuses, e.g. servo-writers

Abstract

A method for writing servo patterns on a hard disk drive disk in a hard disk drive assembly. The assembly includes a disk having at least one magnetic surface in which a reference pattern has been written, determining a reference track. Also included is an actuator having a shaft engaged with the disk to provide rotational motion to the disk, an actuator arm, and a micro-actuated read/write head mounted on the actuator arm. The method includes the following steps. First, the read/write head is used to position the actuator arm at a first fixed position over the reference track. The actuator arm is maintained at the first fixed position while the read/write head is used to write a second servo pattern, determining a second track. The read/write head is used to position the actuator arm at a second fixed position over the second track. Then, the actuator arm is maintained at the second fixed position while the read/write head is used to write a third servo pattern.

Claims

1. A method for writing servo patterns on a disk in a hard disk drive assembly, said assembly comprising

a disk having at least one magnetic surface in which a reference pattern has been written, determining a reference track,

an actuator having a shaft engaged with said disk to provide rotational motion to said disk,

an actuator arm, and

a micro-actuated read/write head on said actuator arm, comprising the steps of:

using said read/write head to position said actuator arm at a first fixed position over said reference track;

maintaining said actuator arm at said first fixed position while displacing said read/write head and using said displaced read/write head to write a second servo pattern, determining a second track displaced from said reference track;

using said read/write head to position said actuator arm at a second fixed position over said second track; and

maintaining said actuator arm at said second fixed position while displacing said read/write head and using said displaced read/write head to write a third servo pattern determining a third track displaced from said second track.

2. A method for writing servo patterns on a hard disk drive disk according to claim 1, further comprising the steps of

using said read/write head to position said actuator arm at further fixed positions over previously written servo patterns determining previously written tracks; and

maintaining said actuator arm at said further fixed positions while using said read/write head to write further servo patterns determining further tracks displaced from said previously written tracks.

3. A method for writing servo patterns on a disk in a hard disk drive assembly, said assembly comprising

a disk, rotatable about a central axis thereof, having at least one magnetic surface,

an actuator having a shaft engaged with said disk to provide rotational motion to said disk about said central axis,

an actuator arm capable of lateral movement across said surface of said disk for positioning over substantially circular tracks thereon, and

a micro-actuated read/write head on said actuator arm, and

a mechanical stop for restraining said actuator arm from lateral movement at a predetermined reference position, comprising the steps of:

positioning said actuator arm at said predetermined reference position against said mechanical stop;

maintaining said actuator arm at said predetermined reference position while using said read/write head to write a reference servo pattern, determining a reference track;

using said read/write head to position said actuator arm at a first fixed position over said reference track;

maintaining said actuator arm at said first fixed position while displacing said read/write head and using said displaced read/write head to write a second servo pattern, determining a second track displaced from said reference track;

using said read/write head to position said actuator arm at a second fixed position over said second track; and

maintaining said actuator arm at said second fixed position while displacing said read/write head and using said displaced read/write head to write a third servo pattern determining a third track displaced from said second track.

4. A method for writing servo patterns on a hard disk drive disk according to claim 3, further comprising the steps of

using said read/write head to position said actuator arm at further fixed positions over previously written servo patterns determining previously written tracks; and

maintaining said actuator arm at said further fixed positions while using said read/write head to write further servo patterns determining further tracks displaced from said previously written tracks.

5. A method for writing servo patterns on a plurality of disks in a hard disk drive assembly, said assembly comprising

a plurality of disks, each having at least one layer of magnetic medium on a surface thereof to form a magnetic surface,

an actuator having a.shaft engaged with said disks to provide rotational motion to said disks,

a plurality of actuator arms, one associated with each of said magnetic surfaces, and

a micro-actuated read/write head on each of said actuator arms, comprising the steps of:

writing a reference servo pattern determining a reference track in at least one of said magnetic surfaces using a write apparatus external to said hard disk drive;

using a first read/write head of a first actuator arm to position said first actuator arm at a first fixed position over said reference track; and

maintaining said first actuator arm at said first fixed position while displacing a second read/write head of a second actuator arm and using said displaced second read/write head to write a second servo pattern, determining a second track displaced from said reference track.

6. A method for writing servo patterns in accordance with claim 5, further comprising the step of:

maintaining said second actuator arm at a second fixed position over said second track while displacing a read/write head of another actuator arm and using said displaced read/write head to write a third servo pattern determining a third track displaced from said second track.

7. A method for writing servo patterns on a plurality of disks in a hard disk drive assembly, said assembly comprising

a plurality of disks, each having at least one layer of magnetic medium on a surface thereof to form a magnetic surface,

an actuator having a shaft engaged with said disks to provide rotational motion to said disks,

a plurality of actuator arms, one associated with each of said magnetic surfaces, and

a micro-actuated read/write head on each of said actuator arms, and

a mechanical stop for restraining a first one of said actuator arms from lateral movement at a predetermined reference position, comprising the steps of:

positioning said first one of said actuator arms at said predetermined reference position against said mechanical stop;

maintaining said first one of said actuator arms at said predetermined reference position while using said read/write head on said first one of said actuator arms to write a reference servo pattern, determining a reference track;

using said read/write head of said first one of said actuator arms to position said first actuator arm at a first fixed position over said reference track; and

maintaining said first actuator arm at said first fixed position while displacing a read/write head of a second actuator arm and using said displaced read/write head to write a second servo pattern determining a second track displaced from said reference track.

8. A method for writing servo patterns on a disk in a hard disk drive assembly, said assembly comprising:

a disk having at least one magnetic surface in which a reference pattern for a reference track has been written,

an actuator having a shaft engaged with said disk to provide rotational motion to said disk,

an actuator arm, and

a dual read/write head assembly on said actuator arm having a first head having at least read capability, and having a second, micro-actuated head having read/write capability, comprising the steps of;

using said first head to position said actuator arm at a first fixed position with said first head over said reference track;

using said first head to maintain said actuator arm at said first fixed position while using said second head to write a second servo pattern determining a second track displaced from said reference track;

while using said first head to maintain said actuator arm at said first fixed position, using said second head to write further servo patterns determining further tracks displaced from said reference track;

using said first head to position said actuator arm at a second fixed position over a track determined by one of said servo patterns written by said second head; and

while using said first head to maintain said actuator arm at said second fixed position, using said second head to write further servo patterns determining further tracks displaced from said one of said servo patterns written by said second head.

9. A method for writing servo patterns on a disk in a hard disk drive assembly, said assembly comprising

a disk, rotatable about a central axis thereof, having at least one magnetic surface,

an actuator having a shaft engaged with said disk to provide rotational motion to said disk about said central axis,

an actuator arm capable of lateral movement across said surface of said disk for positioning over substantially circular tracks thereon,

a dual read/write head assembly on said actuator arm having a first head having at least read capability, and a second, micro-actuated head having read/write capability, and

a mechanical stop for restraining said actuator arm from lateral movement at a predetermined reference position, comprising the steps of:

positioning said actuator arm at said predetermined reference position against said mechanical stop;

maintaining said actuator arm at said predetermined reference position while using said first head to write a reference servo pattern, determining a reference track;

using said first head to position said actuator arm at a first fixed position with said first head over said reference track;

using said first head to maintain said actuator arm at said first fixed position while displacing said second head and using said displaced second head to write a second servo pattern, determining a second track displaced from said reference track;

using said first head to position said actuator arm at a second fixed position with said first head over said second track; and

maintaining said actuator arm at said second fixed position while displacing said second head and using said displaced second head to write a third servo pattern determining a third track displaced from said second track.

10. A method for writing servo patterns on a plurality of disks in a hard disk drive assembly, said assembly comprising

a plurality of disks, each having at least one layer of magnetic medium on a surface thereof to form a magnetic surface,

an actuator having a shaft engaged with said disks to provide rotational motion to said disks,

a plurality of actuator arms in fixed spatial relation with respect to one another, one associated with each of said magnetic surfaces, and

a dual read/write head on each of said actuator arms having a first head having at least read capability, and having a second, micro-actuated head having read/write capability, comprising the steps of:

writing a reference servo pattern determining a reference track in at least one of said layers of magnetic medium using a write apparatus external to said hard disk drive;

using a first head of a first actuator arm to position said first actuator arm at a first fixed position over said reference track;

while maintaining said first actuator arm at said first fixed position, positioning a second head of one of said actuator arms at a position suitable for writing a second servo pattern determining a second track on one of said layers of magnetic medium, said second track being displaced from said reference track;

writing said second servo pattern determining said second track;

positioning said second head at additional positions for the writing of further servo patterns, determining further tracks in said layers of magnetic medium, and writing said further servo patterns determining said further tracks displaced from said reference track;

using said first head to position said first actuator arm at a second fixed position over a temporary reference track determined by said servo patterns written by said second head; and

while maintaining said first actuator arm at said second fixed position, positioning a second head of one of said actuator arms at additional positions for the writing of further servo patterns and writing said further servo patterns determining further tracks displaced from said temporary reference track.

11. A method for writing servo patterns on a plurality of disks in a hard disk drive assembly, said assembly comprising

a plurality of disks, each having at least one layer of magnetic medium on a surface thereof to form a magnetic surface,

an actuator having a shaft engaged with said disks to provide rotational motion to said disks,

a plurality of actuator arms in fixed spatial relation with respect to one another, one associated with each of said magnetic surfaces,

a dual read/write head on each of said actuator arms having a first head having at least read capability, and having a second, micro-actuated head having read/write capability, and

a mechanical stop for restraining a first one of said actuator arms from lateral movement at a predetermined reference position, comprising the steps of:

positioning said first one of said actuator arms at said predetermined reference position against said mechanical stop;

maintaining said first one of said actuator arms at said predetermined reference position while using a first head of one of said actuator arms to write a reference servo pattern, determining a reference track;

using said first head of said one of said actuator arms to position said one of said actuator arms at a first fixed position over said reference track;

.

while maintaining said one of said actuator arms at said first fixed position, positioning a second head of one of said actuator arms at a position suitable for writing a second servo pattern, determining a second track on one of said layers of magnetic medium displaced from said reference track;

writing said second servo pattern determining said second track;

positioning said second head at additional positions for the writing of further servo patterns determining further tracks in said layers of magnetic medium displaced from said reference track and writing said further servo patterns determining said further tracks;

using a first head of one of said actuator arms to position said one of said actuator arms at a second fixed position over a temporary reference track determined by said servo patterns written by said second head; and

positioning a second head of one of said actuator arms at additional positions for the writing of further servo patterns determining further tracks displaced from said temporary reference track and writing said further servo patterns determining said further tracks.

12. A method for writing servo patterns on a disk in a hard disk drive assembly, said assembly comprising

a disk having at least one recordable surface in which a reference pattern has been written, determining a reference track,

an actuator having a shaft engaged with said disk to provide rotational motion to said disk,

an actuator arm, and

a micro-actuated read/write head on said actuator arm, comprising the steps of:

using said read/write head to position said actuator arm at a first fixed position over said reference track;

maintaining said actuator arm at said first fixed position while displacing said read/write head and using said displaced read/write head to write a second servo pattern, determining a second track displaced from said reference track.

13. A method for writing servo patterns on a hard disk drive disk according to claim 12, further comprising the step of

maintaining said actuator arm at said first fixed position while displacing said read/write head and using said displaced read/write head to write a third servo pattern determining a third track displaced from said reference track.

14. A method for writing servo patterns on a hard disk drive disk according to claim 13, further comprising the steps of

positioning said head at additional positions for the writing of further servo patterns, determining further tracks in said layers of magnetic medium, and writing said further servo patterns determining said further tracks displaced from said reference track;

using said head to position said actuator arm at a second fixed position over a temporary reference track determined by said servo patterns written by said head; and

while maintaining said actuator arm at said second fixed position, positioning said head at additional positions for the writing of further servo patterns and writing said further servo patterns determining further tracks displaced from said temporary reference track.

15. A method for writing servo patterns on a disk in a hard disk drive assembly, said assembly comprising

a disk having at least one recordable surface in which a reference pattern has been written, determining a reference track,

an actuator having a shaft engaged with said disk to provide rotational motion to said disk,

an actuator arm having a movable end capable of radial movement across said disk,

a first micro-actuated read/write head on the movable end of said actuator arm, and

a second micro-actuated read/write head on the movable end of said actuator arm capable of displacement relative to said actuator arm, and comprising the steps of:

using said first read/write head to position said actuator arm at a first fixed position over said reference track;

maintaining said actuator arm at said first fixed position while displacing said second read/write head and using said displaced second read/write head to write a second servo pattern, determining a second track displaced from said reference track.

16. A method for writing servo patterns on a disk in a hard disk drive assembly, said assembly comprising

a plurality of disks each having at least one recordable surface in at least one of which a reference pattern has been written, determining a reference track,

an actuator having a shaft engaged with said disk to provide rotational motion to said disks,

a first actuator arm having a movable end capable of radial movement across one of said disks,

a second actuator arm having a movable end capable of radial movement across another one of said disks,

a first micro-actuated read/write head on the movable end of said first actuator arm, and

a second micro-actuated read/write head on the movable end of said second actuator arm capable of displacement relative to said actuator arm, and comprising the steps of:

using said first read/write head to position said first actuator arm at a first fixed position over said reference track, establishing a second fixed position for said second actuator arm;

maintaining said second actuator arm at said second fixed position while displacing said second read/write head and using said displaced second read/write head to write a second servo pattern, determining a second track displaced from said reference track.