Magnetic alignment marking of hard disks
AssigneeSeagate Technology LLC
InventorsDavid S. Kuo, Jason Pressesky, Dan Nguyen
Life of this patent
Estimating the term…
Abstract
Magnetic alignment marks are recorded on a recording surface of a magnetic hard disk to mark the location where the disk is abutted against the hub of the spindle of a multiple-disk servo-writer. The alignment marks for each recording surface may be different so as to distinguish between top and bottom disk surfaces so that when the discs are assembled onto the spindle of a disk drive they may be assembled with the proper orientation, i.e., the top surface is mounted “up.” The marks may be large, low frequency patterns that are both written and detected by non contact means other than the servo-track writer's or the disk drive's heads.
Claims20
A method of recording alignment marks on a magnetic hard disk, comprising:
- magnetically recording an identifiable pattern on at least a first surface of a magnetic hard disk, the location of the pattern corresponding to the inner diameter location of the hard disk inner diameter which abuts against a servo-writer's spindle hub during servo-write of the surface.
A method of assembling a hard disk drive, comprising:
- mounting a magnetic hard disk having a magnetic alignment mark recorded thereon on a hard disk drive spindle;
- and
- biasing the hard disk inner diameter against said hard disk drive spindle such that the inner diameter abuts the spindle at an inner diameter location that has a predefined relationship with said magnetic alignment mark.
A method of writing servo patterns on a magnetic hard disc, comprising:
- mounting one or more magnetic hard discs on a servo writer spindle hub;
- biasing said one or more magnetic hard disks such that their inner diameter abuts the hub at an inner diameter abutment location;
- magnetically marking at least one surface of each of said magnetic hard disks with an identifiable pattern at a location on said surface that has a predetermined relationship with said abutment location.
A magnetic hard disk, comprising:
- a magnetic hard disk having an inner diameter location that is the point on the inner diameter that was abutting a servo-writer spindle hub when a servo pattern was written on to the disk;
- and
- magnetically readable means for marking the location of said abutment location.
Dependencies are inferred from the claim text.