Dynamic magnetic information storage or retrieval – Monitoring or testing the progress of recording
Reexamination Certificate
2007-02-20
2007-02-20
Sniezek, Andrew L. (Department: 2627)
Dynamic magnetic information storage or retrieval
Monitoring or testing the progress of recording
C360S075000
Reexamination Certificate
active
11320425
ABSTRACT:
A system and method for calibrating and controlling a magnetic recording disk drive fly-height actuator uses the signal from the magnetoresistive (MR) read head to determine head-disk contact (HDC). The MR signal is measured over a low-frequency range, with the slider out-of-contact with the disk, to develop a reference value. The MR signal is then measured over the same low-frequency range and if it exceeds the reference value by some predetermined amount, this is an indication of HDC. The fly-height actuator control signal value for HDC is recorded and thus corresponds to a head-disk spacing of zero. The calibration method also determines the sensitivity of head-disk spacing to the fly-height actuator control signal by measuring a series of MR read signal amplitudes for a corresponding series of control signals. The fly-height actuator is calibrated from the sensitivity and the value of control signal that results in zero head-disk spacing, and can then be controlled to move the head to a desired fly height and maintain it at the desired fly height.
REFERENCES:
patent: 5021906 (1991-06-01), Chang et al.
patent: 5130866 (1992-07-01), Klaassen et al.
patent: 5276573 (1994-01-01), Harada et al.
patent: 5455730 (1995-10-01), Dovek et al.
patent: 5991113 (1999-11-01), Meyer et al.
patent: 6344949 (2002-02-01), Albrecht et al.
patent: 6407874 (2002-06-01), Smith et al.
patent: 6417981 (2002-07-01), Smith
patent: 6459539 (2002-10-01), Carlson et al.
patent: 6570730 (2003-05-01), Lewis et al.
patent: 6611399 (2003-08-01), Mei et al.
patent: 6671110 (2003-12-01), Baba et al.
patent: 6674590 (2004-01-01), Ottesen et al.
patent: 6717776 (2004-04-01), Boutaghou
patent: 6735027 (2004-05-01), Helsel et al.
patent: 6765745 (2004-07-01), Smith et al.
patent: 6775103 (2004-08-01), Kang et al.
patent: 6801376 (2004-10-01), Smith
patent: 6865040 (2005-03-01), Fayeulle et al.
patent: 2001/0050826 (2001-12-01), Helsel et al.
patent: 2003/0067698 (2003-04-01), Dakroub et al.
patent: 2003/0156340 (2003-08-01), Jen et al.
patent: 2004/0179299 (2004-09-01), Sasaki et al.
patent: 2004/0218302 (2004-11-01), Maat
patent: 2004/0240099 (2004-12-01), Brannon et al.
patent: 2004/0240109 (2004-12-01), Hamann et al.
patent: 2005/0013036 (2005-01-01), Yang
patent: 2005/0024761 (2005-02-01), Lou et al.
patent: 2005/0024775 (2005-02-01), Kurita et al.
patent: 2005/0046982 (2005-03-01), Liu et al.
patent: 2005/0046985 (2005-03-01), Morinaga et al.
patent: 2005/0046988 (2005-03-01), Suk
patent: 2005/0046995 (2005-03-01), Lille
patent: 2005/0052773 (2005-03-01), Suk
patent: 2005/0057841 (2005-03-01), Stuver et al.
patent: 2005/0094299 (2005-05-01), Tokizono et al.
patent: 2005/0094303 (2005-05-01), Chan
patent: 2006/0139789 (2006-06-01), Yang
patent: 2004335069 (2004-11-01), None
Li et al., “Real-Time Method to Measure Head Disk SpacingVariation Under Vibration Conditions”, IEEE Trans on Instrumentation and Meas, vol. 52, No. 3, Jun. 2003, pp. 916-920.
Tanaka et al., “Slider Dynamics During Continuous Contact with Textured and Smooth Disks in Ultra Low Flying Height”, IEEE Trans Magn, vol. 37, No. 2, Mar. 2001, pp. 906-911.
Khurshudov et al., “Head-disk contact detection in the hard-disk drives”, Wear 255 (2003) 1314-1322.
Hughes, “Improved Disk Drive Failure Warnings”, IEEE Trans Reliability, Sep. 2002, pp. 1-10.
Nikitin, et al. “Spatial and temporal profiling of protrusion in magnetic recording heads”, IEEE Transactions on Magnetics, vol. 40, No. 1, Jan. 2004, pp. 326-331.
Che Xiaodong
Huang Weidong
Lam Terence Tin-Lok
Lin Zhong-heng
Shteyn Alex
Berthold Thomas R.
Sniezek Andrew L.
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