Head-medium contact detection using an oscillating electromagnetic force

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United States of America Patent

PATENT NO 9721603
SERIAL NO

15237878

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Abstract

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An apparatus comprises circuitry configured to apply an AC signal having a frequency to one of a slider of a recording head and a magnetic recording medium. The applied AC signal causes an oscillation in an electrostatic force and clearance between the slider and the medium at the frequency of the AC signal. A thermal sensor is configured to generate a sensor signal at the AC signal frequency in response to sensing changes in temperature resulting from the oscillating clearance. A detector is coupled to the circuitry and the thermal sensor. The detector is configured to detect one or both of head-medium spacing changes and head-medium contact using a phase of a first harmonic or an amplitude of a second harmonic of the thermal sensor signal.

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Patent Owner(s)

Patent OwnerAddress
SEAGATE TECHNOLOGY LLCCALIFORNIA USA

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Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Geer, Andrea L Shoreview, US 1 4
Macken, Declan Eden Prairie, US 91 1126
Olson, Daniel W St. Louis Park, US 14 82

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