Dynamic magnetic information storage or retrieval – Automatic control of a recorder mechanism – Controlling the head
Reexamination Certificate
1999-03-03
2001-10-02
Sniezek, Andrew L. (Department: 2651)
Dynamic magnetic information storage or retrieval
Automatic control of a recorder mechanism
Controlling the head
C360S053000, C360S063000
Reexamination Certificate
active
06297925
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a method for eliminating a wiggle of a magnetic head in a hard disk drive.
DESCRIPTION OF THE RELATED ART
A hard disk drive writes data on a hard disk through a magnetic head and reads the written data After the data is written, the head core and the circumference thereof in the magnetic head may be often in a charged state, i.e., electrically non-neutral state, which is called a wiggle. This phenomenon is referred to as a pinning of a particle component domain in the magnetic head. If such a charging phenomenon occurs in the magnetic head, a noise is generated during the data read by the magnetic head, which is called a wiggle noise.
To prevent the generation of the wiggle noise, it is necessary to eliminate the wiggle by supplying current to the magnetic head where the charging phenomenon has occurred, which is a bimodal retry or a remote write operation. If the remote write operation is performed, the pinned domain is recovered to a normal state and thus the wiggle is prevented from being generated. In eliminating the wiggle, the remote write operation must be performed when the magnetic head is positioned in a parking area. Otherwise, the remote write operation destroys the data or servo information which is written on the disk positioned below the magnetic head.
U.S. Pat. No 5,600,217 for a CMOS Disk Drive Motor Control Circuit Having Back-EMF Regulator Circuitry to Bartlett discloses parking the head of a disk drive to prevent back-EMF from the disk drive motor from exceeding a predetermined level. However, I have not seen a reference which parks a magnetic head when the magnetic head is in a charged state or wiggle. Nor have I seen a device which uses the second magnetic head to determine the position of the first magnetic head when it is desirable for the first magnetic head to be located in the parking area.
SUMMARY OF THE INVENTION
To solve the above problems, it is an object of the present invention to provide a method for eliminating wiggle, by which a remote write operation is performed in a state where a magnetic head is definitely positioned in a parking area.
To accomplish the above object of the present invention, there is provided a method for eliminating a wiggle of a magnetic head in a hard disk drive by moving a first magnetic head to a parking area when wiggle is generated in the first magnetic head being in use; checking whether the first magnetic head is positioned in the parking area, using a second magnetic head at which the wiggle is not generated; and eliminating the wiggle by supplying current to the first magnetic head.
Preferably, the eliminating step further comprises the step of supplying current to allow the first magnetic head to move to the parking area.
REFERENCES:
patent: 5241438 (1993-08-01), Matsushima
patent: 5600217 (1997-02-01), Bartlett
patent: 5808825 (1998-09-01), Okamura
patent: 5872670 (1999-02-01), Ataee
patent: 5940234 (1999-08-01), Wilson et al.
patent: 6118607 (2000-09-01), Jung
patent: 6172836 (2001-01-01), Bang
patent: 6172839 (2001-01-01), Ahn
patent: 6172855 (2001-01-01), Kim
Bushnell , Esq. Robert E.
Samsung Electronics Co,. Ltd.
Sniezek Andrew L.
LandOfFree
Method for eliminating wiggle of magnetic head in hard disk... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for eliminating wiggle of magnetic head in hard disk..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for eliminating wiggle of magnetic head in hard disk... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2600024