Disk drive with controlled actuator oscillation for release of head carriers

Claim 2

A data recording disk drive comprising: at least one data disk; a motor spindle connected to the disk for rotating the disk; a transducer for writing data to or reading data from the disk; a carrier supporting the transducer; a voice coil motor actuator connected to the carrier for moving the carrier generally radially across the disk so the transducer may access different regions of data on the disk; means coupled to the coil of the voice coil motor actuator for applying a train of alternating positive and negative current pulses to the coil of the voice coil motor to oscillate the carrier radially in and out, the positive current pulses having a pulse duration or an amplitude different from the pulse duration or amplitude, respectively, of the negative current pulses to simultaneously move the oscillating carrier in a net radial direction across the disk when the disk is not rotating at its operating speed; and means for supporting the spindle motor and voice coil motor actuator.

Claim 3

The disk drive according to claim 1 further comprising means coupled to the pulse train application means for sensing when the disk is rotating at its operating speed, and means responsive to the sensing means for terminating oscillation of the carrier.

Claim 4

The disk drive according to claim 1 further comprising means attached to the spindle motor and voice coil motor actuator supporting means for unloading the carrier from the disk when the disk drive is not operating, and wherein the train of alternating current pulses causes the carrier to move generally radially across the disk to the unloading means.

Claim 5

The disk drive according to claim 1 further comprising a carrier landing zone located on the disk, and wherein the train of alternating current pulses causes the carrier to move across the disk to the landing zone.

Claim 6

The disk drive according to claim 1 wherein the carrier is an air-bearing slider.

Claim 7

The disk drive according to claim 1 wherein the disk has a continuous liquid film on its surface and further comprising means for maintaining the carrier generally in contact with the liquid film when the disk is rotating at its operating speed.

Claim 8

The disk drive according to claim 1 wherein the pulse train application means comprises means for applying the pulses at a frequency that varies with time.

Claim 9

The disk drive according to claim 7 wherein the means for applying the pulses at a varying frequency comprises means for decreasing the frequency from an initial frequency.

Claim 10

The disk drive according to claim 8 wherein the actuator has a resonant frequency when the carrier is stuck to the disk, and wherein the initial frequency is equal to or higher than said actuator resonant frequency.

Claim 11

The disk drive according to claim 1 wherein the pulse train application means comprises means for applying the pulses at an amplitude that varies with time.

Claim 12

A magnetic recording disk drive comprising: a magnetic recording disk having a region for the recording of data; a spindle motor connected to the disk for rotating the disk; a transducer for writing data to or reading data from the disk; a carrier for supporting the transducer; a voice coil motor (VCM) actuator for moving the carrier generally radially across the disk; a suspension connecting the carrier to the actuator for maintaining the carrier near the surface of the disk when the disk is rotating at its operating speed; means for parking the carrier when the disk is not rotating at its operating speed; and means responsive to an error condition indicating that the spindle motor has not started for applying a train of alternating positive and negative current pulses to the coil of the voice coil motor to oscillate the carrier radially in and out, the positive current pulses having a pulse duration or an amplitude different from the pulse duration or amplitude, respectively, of the negative current pulses to simultaneously move the oscillating carrier across the disk toward the parking means.

Claim 13

A magnetic recording disk drive comprising: a magnetic recording disk having a region for the recording of data; a spindle motor connected to the disk for rotating the disk; a transducer for writing data to or reading data from the disk; a carrier for supporting the transducer; a voice coil motor (VCM) actuator for moving the carrier generally radially across the disk; a suspension connecting the carrier to the actuator for maintaining the carrier near the surface of the disk when the disk is rotating at its operating speed; means for parking the carrier when the disk is not rotating at its operating speed; and means responsive to an error condition indicating that the spindle motor has not started for applying a train of alternating positive and negative current pulses to the coil of the voice coil motor to oscillate the carrier radially in and out, the positive current pulses having a pulse duration or an amplitude different from the pulse duration or amplitude, respectively, of the negative current pulses to simultaneously move the oscillating carrier across the disk toward the parking means.

Claim 14

The disk drive according to claim 11 wherein the carrier parking means comprises means for supporting the carrier away from the disk.

Claim 15

The disk drive according to claim 11 wherein the carrier parking means comprises a carrier landing zone located on the disk.

Claim 16

The disk drive according to claim 11 wherein the carrier is an air-bearing slider.

Claim 17

The disk drive according to claim 11 wherein the disk has a continuous liquid film on its surface, and wherein the suspension comprises means for maintaining the carrier generally in contact with the liquid film when the disk is rotating.

Claim 18

The disk drive according to claim 11 wherein the pulse train application means comprises means for applying the pulses at a frequency that varies with time.

Claim 19

The disk drive according to claim 16 wherein the means for applying tile pulses at a varying frequency comprises means for decreasing the frequency from an initial frequency.

Claim 20

The disk drive according to claim 17 further comprising a rigid arm connecting the coil of the VCM to the suspension and wherein the coil of the VCM with attached arm and suspension has a resonant frequency when the carrier is stuck to the disk, and wherein said initial frequency is equal to or higher than said resonant frequency.

Claim 21

The disk drive according to claim 11 wherein the pulse train application means comprises means for applying the pulses at an amplitude that varies with time.

Claim 22

The disk drive according to claim 11 wherein the pulse train application means comprises means for applying the pulses at a frequency and amplitude that decrease with time.

Claim 23

A magnetic recording disk drive comprising: a plurality of magnetic recording disks, each disk having at least one disk surface having a region for the recording of data; a spindle motor connected to the disks for rotating the disks; means for generating an error condition signal when the spindle motor is not rotating at its operating speed after power bas been applied to the spindle motor; a plurality of transducers for writing data to or reading data from the disks; a plurality of carriers, each carrier supporting at least one transducer; a voice coil motor (VCM) rotary actuator for moving the carriers generally radially across their associated disk surfaces; a plurality of suspensions, each suspension connected to an associated carrier, for maintaining the carriers near the surfaces of their associated disks when the disks are rotating at their operating speed; at least one rigid arm connecting the coil of the VCM to the suspensions, the system of the coil-arm-suspension carriers having a resonant frequency when all of the carriers are stuck to their associated disk surfaces; means for parking the carriers when the disks are not rotating at their operating speed; and means responsive to the error condition signal for applying a train of alternating current pulses to the coil of the VCM to oscillate the carriers radially in and out and simultaneously move them in a net radial direction across the disks toward the parking means, the pulse train application means including means for applying the pulses at a decreasing frequency commencing with an initial frequency equal to or greater than said resonant frequency.

Claim 24

A magnetic recording disk drive comprising: a plurality of magnetic recording disks, each disk having at least one disk surface having a region for the recording of data; a spindle motor connected to the disks for rotating the disks; means for generating an error condition signal when the spindle motor is not rotating at its operating speed after power bas been applied to the spindle motor; a plurality of transducers for writing data to or reading data from the disks; a plurality of carriers, each carrier supporting at least one transducer; a voice coil motor (VCM) rotary actuator for moving the carriers generally radially across their associated disk surfaces; a plurality of suspensions, each suspension connected to an associated carrier, for maintaining the carriers near the surfaces of their associated disks when the disks are rotating at their operating speed; at least one rigid arm connecting the coil of the VCM to the suspensions, the system of the coil-arm-suspension carriers having a resonant frequency when all of the carriers are stuck to their associated disk surfaces; means for parking the carriers when the disks are not rotating at their operating speed; and means responsive to the error condition signal for applying a train of alternating current pulses to the coil of the VCM to oscillate the carriers radially in and out and simultaneously move them in a net radial direction across the disks toward the parking means, the pulse train application means including means for applying the pulses at a decreasing frequency commencing with an initial frequency equal to or greater than said resonant frequency.

Claim 25

The disk drive according to claim 21 wherein the carrier parking means comprises means for supporting the carriers away from their associated disk surfaces.

Claim 26

The disk drive according to claim 21 wherein the carrier parking means comprises a carrier landing zone located on each of the associated disk surfaces away from the data region on each of said disk surfaces.

Claim 27

The disk drive according to claim 21 wherein the carriers are air-bearing sliders.

Claim 28

The disk drive according to claim 21 wherein each of the disk surfaces has a continuous liquid film, and wherein each of the suspensions comprises means for maintaining its associated carrier generally in contact with the liquid film on its associated disk surface when the disks are rotating at their operating speed.

Claim 29

The disk drive according to claim 21 wherein the pulse train application means to move the carriers simultaneously with their oscillation includes means for applying the pulses with a current amplitude that decreases with time.

Claim 30

The disk drive according to claim 21 wherein the pulse train application means to move the carriers simultaneously with their oscillation includes means for applying positive current pulses at a different amplitude than negative current pulses, whereby a net force is applied to the coil to move the connected carriers in a generally radial direction across the disks.

Claim 31

The disk drive according to claim 21 wherein the pulse train application means to move the carriers simultaneously with their oscillation includes means for applying positive current pulses with a fixed-pulse duration and negative current pulses of the same amplitude as the positive current pulses and with a fixed-pulse duration different than the duration the positive current pulses, whereby a net force is applied to the coil to move the connected carriers in a generally radial direction across the disks.