摘要:
A slider head assembly is provided which includes a slider head for reading/writing data on the surface of a rotating disc. The slider head is disposed in spaced relationship with respect to the disc for read/write (R/W) operations. The slider head assembly is comprised of a body portion having an essentially planar surface positioned to co-act with the surface of the disc with a proximal end and a distal end. The proximal end or trailing slider surface of the head assembly has a read/write element thereat. The distal end or leading slider surface of the assembly has an actuation device mounted thereon, having a surface the position of which can be modified by an external signal to change the position of the head with respect to the planar or air bearing surface (ABS) of the head assembly. This will change the characteristics of the boundary layer of air between the rotating disc and the head, causing the head assembly to move closer to or farther from the rotating disc when actuated by the external signal. A preferred embodiment is a patterned heating element which selectively heats the edge of the leading surface of the slider to cause position modification of the device. The invention also contemplates the head assembly in combination with the rotating disc and a method of controlling the height of the head assembly with respect to the rotating disc.
摘要:
A disk drive is disclosed comprising a head actuated over a disk surface, the head comprising a fly height actuator for controlling a fly height of the head, and a ramp for parking the head. A ramp procedure is executed by applying a control signal to the fly height actuator to decrease the fly height and receiving a corresponding fly height signal, and detecting whether the head is on the ramp in response to the fly height signal.
摘要:
A disk drive is disclosed comprising a head actuated over a disk, and a fly height actuator operable to control a fly height of the head over the disk. A periodic control signal is applied to the fly height actuator, a frequency response of a touchdown metric at a frequency of the periodic control signal is measured, and a touchdown event is detected in response to the frequency response of the touchdown metric.
摘要:
A recording head for a disk drive with a load/unload mechanism has an air bearing on one surface. The air bearing comprises a patterned set of three air bearing pads, at least five shallow pockets and one deep pocket. A narrow gap extends from the deep pocket and separates leading ones of the air bearing pads and shallow pockets from each other. The air bearing pads have unique, step-shaped geometry and the rear pad is virtually free of any shallow area. This configuration gives the air bearing superior performance characteristics over prior art designs with load/unload mechanisms.
摘要:
A novel method of selecting an electrical power, to be applied to a subject head-based flying height actuator during operation of a disk drive, is disclosed and claimed. A touch-down power for each of a plurality of representative heads is detected. A relationship between back-off power and touchdown power for the plurality of representative heads is estimated. A touch-down power for the subject head is detected. A back-off power for the subject head is calculated using the estimated relationship and the detected touch-down power for the subject head. The electrical power to be applied to the subject head-based flying height actuator is selected to be equal to the detected touch-down power for the subject head minus the calculated back-off power for the subject head.
摘要:
A dual etch depth slider air bearing surface includes a front pad disposed along the front and partially along the sides of the slider and a rear pad partially disposed along the rear of the slider, wherein a skewed center rail connects the front pad to the rear pad. Extending above the rear pad is a V-shaped ABS pad and extending above the front pad are two leading edge ABS pads that are separated by a channel towards the longitudinal center of the slider. The design enables the slider to fly much higher over the landing zone of the disk than at the data zone and provides for a steep take off profile followed by a rapid descend over the data zone.
摘要:
A slider air bearing design and method providing “writing of laser field” (WOLF) measurement without substantial fly height affect. A central pad at ion-mill height is formed in the cavity between the side rails and rear pad. The central pad allows correlation of WOLF crown measurement values with crown measurements obtain via optical interferometer. Also, the central pad provides good reflective areas while preventing degradation in fly height performance due to the rear pad geometry constraints required by the WOLF measurement process.
摘要:
A disk drive is disclosed comprising a disk, a head actuated over the disk, and control circuitry operable to generate a fly height control signal. A fly height of the head is measured, and the measured fly height is combined with a target fly height and a feedforward signal, wherein the feedforward signal is generated according to: a1·cos(2πn1k/N)+b1·sin(2πn1k/N) where a1 and b1 are coefficients and 2πn1k/N represents a frequency of a repeatable disturbance in the fly height of the head.
摘要:
In one embodiment and method of the present invention, an optical interference fly height (FH) test apparatus for measuring FH is disclosed, in accordance with an embodiment of the present invention, to include a slider, a transparent disk, means for directing a light beam directed between the slider and the disk, and means for iteratively measuring an estimated FH using at least two points of measurement on the slider when the slider is moved away from the disk at a pitch angle, wherein the estimated FH is computed as a function of the pitch angle and during each iteration, a previously-estimated FH is used to converge the estimated FH so that the estimated FH is within a predetermined range from the actual FH.
摘要:
A dual depth slider air bearing surface that enables the slider to achieve a ramp fly height profile near the textured landing zone of a disk. The air bearing slider includes a slider body on which a U-shaped leading ABS pad is defined near and along a leading edge (relative to a moving recording medium) and partially along each side of the slider body. A front step pad extends from the leading edge section of the leading ABS pad to the leading edge of the slider body, at a reduced height relative to the height of the ABS pad. An asymmetric rear pad is defined along a longitudinal axis of the slider body and proximate to a trailing edge of the slider body. Extending above the rear pad is a trailing ABS pad, which has an asymmetric profile with respect to the longitudinal axis of the slider. The trailing ABS pad has a curved bowing profile towards the front of the slider body on the leading edge side of the trailing ABS pad.