Seagate Technology Incorporated

Lee Clifford Knippenberg

Michael Thomas Johnson

Adam Karl Himes

Dongming Liu

Lin Zhou

Zine-Eddine Boutaghou

Wayne Allen Bonin

Jason Wayne Riddering

Anthony Pascal Sannino

Jorge Vicente Hanchi

Ram Mohan Rao

Derek A Lewis

Lijun Fu

A method of detecting a contact between a transducing head and a storage medium is provided. The method applies an input signal, having a select power level and known frequency, to an actuator for actuating the head. An output signal is obtained in response to the input signal. At least one signal component is extracted from the output signal at the same or a harmonic of the same known frequency as the input signal applied to the actuator. Whether the at least one extracted signal component indicates a contact between the head and the medium is determined. The power level of the applied wave pattern is increased incrementally until the extracted signal component indicates a contact between the head and the storage medium.

Contact detection

A method of detecting contact between a transducing head-carrying slider and a rotatable disc is performed by applying an electrostatic voltage between the slider and the disc and monitoring current flow across an interface between the slider and the disc. The monitored current flow across the interface between the slider and the disc is analyzed to detect contact between the slider and the disc.

In-situ monitoring of proximity and contact between a slider and a disc in a disc drive

A disc drive includes a head with an air bearing surface that provides a fly height spacing. A fly height spacing control system provides a control signal to a head electrical connection on a head and a disco electrical connection on a disc. Fly height is controlled electrostatically. A disconnect circuit couples the control signal to the disc electrical connection. The disconnect circuit provides a disconnection of the control signal when contact is sensed. A contact sensor senses an electrical current component of the control signal that indicates contact between the head and the disc.

Contact detection and calibration for electrostatic fly height control in a disc drive

To allow for adjusting the fly height of a read/write head carried by a slider, a shear transducer is added to the slider. The shear transducer comprises a layer of piezoelectric material added to the slider so that the portion of the slider carrying the read/write head can be moved when the shear transducer is sheared. To cause the shear transducer to shear, a voltage is applied across the piezoelectric layer. To control the movement of the transducer, a closed-loop control system is used. The control system senses the spacing between the read/write head and the disc surface, compares the sensed spacing to a desired spacing, and adjusts the voltage applied to the shear transducer to reduce the difference between the actual and desired spacing.

Shear-based transducer for HDD read/write element height control

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Burnsville, MN, United States of America

Lee Clifford Knippenberg