Abstract: Storing data to a storage medium with a device that has moving parts supported by a bearing and which maintains separation between opposing bearing surfaces in the bearing with a pressurized working fluid.

Abstract: Storing data to a storage medium with a device that has moving parts supported by a bearing and which maintains separation between opposing bearing surfaces in the bearing with a pressurized working fluid.

Abstract: A servo track writer assembly and method are provided for recording servo pattern information on a disc. The servo track writer assembly includes a spindle assembly, an actuator assembly and a servo recording head. The spindle assembly has a hub, which supports the disc and a spindle motor for rotating the hub. The actuator assembly has an actuator arm supported by an actuator bearing for positioning the actuator arm relative to the disc. At least one of the spindle motor and the actuator bearing has a gas-lubricated bearing with a working fluid, which includes helium. The servo recording head is supported by the actuator arm relative to the disc to record the servo pattern information on the disc as the spindle motor rotates the disc and the actuator bearing positions the actuator arm.

Abstract: A method for writing servo information to a data storage medium adapted for use in a data storage device wherein the medium is operably moved in ambient air at a nominal speed in data reading and writing relationship with a data transfer member. In one embodiment the method for writing comprises placing the medium adjacent a data transfer member in an enclosure containing a gaseous environment as a selected state; moving the medium to impart velocity to the gaseous environment which, in turn, impacts the data transfer member with forces flying the writing member at a first fly height from the medium; and subsequently introducing a gas having a density less than the gaseous environment into the enclosure, thereby responsively reducing the fly height of the writing member to a selected height less than the first fly height.

Abstract: A servo track writer assembly and method are provided for recording servo pattern information on a disc. The servo track writer assembly includes a spindle assembly, an actuator assembly and a servo recording head. The spindle assembly has a hub, which supports the disc and a spindle motor for rotating the hub. The actuator assembly has an actuator arm supported by an actuator bearing for positioning the actuator arm relative to the disc. At least one of the spindle motor and the actuator bearing has a gas-lubricated bearing with a working fluid, which includes helium. The servo recording head is supported by the actuator arm relative to the disc to record the servo pattern information on the disc as the spindle motor rotates the disc and the actuator bearing positions the actuator arm.

Abstract: A method includes selecting a subset of predictive frequencies from a set of disc drive frequencies consisting essentially of operational driving frequencies in the disc drive and system resonance frequencies in the disc drive. Correlation constants are determined that correlate sound power to mechanical vibration magnitudes at each of the frequencies in the subset of predictive frequencies. The method further includes acquiring mechanical vibration data from the disc drive while operating the disc drive and determining predictive vibration magnitudes at each of the frequencies in the subset of predictive frequencies from the mechanical vibration data. Finally, the method includes determining an estimated acoustic sound power value for the disc drive from the determined correlation constants and the predictive vibration magnitudes. A testing system determines an estimated acoustic sound power value for a subject disc drive from predetermined correlation constants and vibration magnitudes.

Abstract: A data storage device stabilization mechanism for a servo track writing (STW) nest is disclosed. The stabilization mechanism comprising a baseplate, at least two fixed restraints on the baseplate adapted to receive and position a data storage device on the baseplate, and at least two clamps on the baseplate. The clamps are operable to move between a first position and a second position. In the first position the clamps engage a data storage device positioned on the baseplate by the fixed restraints and apply a restraining force on the data storage device in a direction perpendicular to the disc rotation axis to dampen rotational movement of the data storage device relative to the baseplate. In the second position, the clamps do not engage the data storage device positioned on the baseplate allowing a data storage device to be positioned or removed easily.

Abstract: In relating rotational vibration stimuli of a mechanical mounting environment to the performance of a disc drive, a method and system are provided of which the steps are selecting a sample disc drive of a drive species and mounting the sample disc drive within the mechanical mounting environment; attaching an accelerometer to the sample disc drive for measuring rotational vibration; inducing a predetermined rotational vibration stimuli into the mechanical mounting; collecting vibration data with the accelerometer for use in determining the rotational vibration index for the mechanical mounting environment; providing a rotational vibration index for the drive species for comparison with the determined rotational vibration index; and comparing the rotational vibration index calculated for the mechanical mounting environment with the rotational vibration index of the drive species to relate the rotational vibration stimuli of the mechanical mounting environment to the performance of the sample disc drive.

Abstract: A method of detecting that a concentration of a low-density gas such as helium in a disc drive is in danger of reaching an unacceptable level includes monitoring a signal varying in response to variations in the concentration of the gas in the disc drive. A criterion is determined based on the signal where the criterion indicates that the gas level is about to reach the unacceptable level. Finally, a flag is set once the criterion is met. A disc drive containing a low-density gas such as helium includes a sensor within the drive that produces a signal responsive to variations in the concentration of the low-density gas in the disc drive. The disc drive also includes a processor that monitors the signal and sets a flag if a predetermined criterion is met.

Abstract: A method of detecting and quantifying head-disc interference in a disc drive includes obtaining a position error signal representing deviation of a head from a track on a disc in the disc drive. A portion of the position error signal is analyzed to produce a signal value that corresponds to a level of head-disc interference in the disc drive. The signal value is compared to a predetermined benchmark value. A head-disc interference detection system is adapted to detect and quantify contact between discs and heads positioned over data surfaces of the discs in disc drives. The system includes a disc drive including a disc and a head positioned over a data surface of the disc. The head is able to produce a position error signal representing deviation of the head from a track of the data surface. The detection system is able to analyze magnitudes of the position error signal to produce a signal value. The detection system is also able to compare the signal value to a predetermined benchmark value.

Abstract: A method includes selecting a subset of predictive frequencies from a set of disc drive frequencies consisting essentially of operational driving frequencies in the disc drive and system resonance frequencies in the disc drive. Correlation constants are determined that correlate sound power to mechanical vibration magnitudes at each of the frequencies in the subset of predictive frequencies. The method further includes acquiring mechanical vibration data from the disc drive while operating the disc drive and determining predictive vibration magnitudes at each of the frequencies in the subset of predictive frequencies from the mechanical vibration data. Finally, the method includes determining an estimated acoustic sound power value for the disc drive from the determined correlation constants and the predictive vibration magnitudes. A testing system determines an estimated acoustic sound power value for a subject disc drive from predetermined correlation constants and vibration magnitudes.

Abstract: A method of detecting that a concentration of a low-density gas such as helium in a disc drive is in danger of reaching an unacceptable level includes monitoring a signal varying in response to variations in the concentration of the gas in the disc drive. A criterion is determined based on the signal where the criterion indicates that the gas level is about to reach the unacceptable level. Finally, a flag is set once the criterion is met. A disc drive containing a low-density gas such as helium includes a sensor within the drive that produces a signal responsive to variations in the concentration of the low-density gas in the disc drive. The disc drive also includes a processor that monitors the signal and sets a flag if a predetermined criterion is met.

Abstract: A contact detector for detecting intermittent contact between a read/write device and a data storage media during data reading and writing operations therebetween in a data storage device. The read/write device is supported upon a moveable support member responsive to a control system for moving the read/write device to selected positions adjacent the data storage media. The data storage media is supported by a motor responsive to the control system for spinning the data storage media to generate air currents that operatively lift and support the read/write device in spatial disposition from the data storage media. The contact detector comprises a receiver circuit comprising a sensor tuned to a selected frequency associated with the data storage device. The selected frequency indicates instances of the read/write device making contacting engagement with the data storage media.

Abstract: A method for evaluating head flight characteristics in a disc drive includes accelerating a disc to an initial rotational velocity sufficient to aerodynamically support a head over the disc at a nominal flying height. A read bias current is applied to the head to generate a readback signal determined in relation to the voltage drop across the head. A thermal asperity threshold level is applied which the readback signal exceeds in response to contact between the head and the disc as the disc rotates. A head touchdown velocity is determined by decelerating the disc to decrease the flying height of the head and detecting subsequent contact between the head and the disc when the readback signal exceeds the thermal asperity threshold level. A head take off velocity is similarly determined by monitoring the head readback signal as the disc is accelerated and lifts off the disc.

Abstract: A method for evaluating head flight characteristics in a disc drive includes placing a non-contact voltmeter (NCV) probe into close proximity to a disc, the probe sensing disc potential in relation to a quantity of electrical charge present on the disc. The disc is accelerated with the head initially remaining in contact with the disc, and the disc potential is monitored until a rotational velocity is achieved sufficient to cause the head to separate from the disc. A head take off velocity is thereafter determined in relation to a detected change in the measured disc potential. A head touchdown velocity is similarly determined by initially accelerating the disc to separate the head therefrom, and then monitoring the disc potential as the disc is decelerated to bring the head back into contact with the disc.

Abstract: In relating rotational vibration stimuli of a mechanical mounting environment to the performance of a disc drive, a method and system are provided of which the steps are selecting a sample disc drive of a drive species and mounting the sample disc drive within the mechanical mounting environment; attaching an accelerometer to the sample disc drive for measuring rotational vibration; inducing a predetermined rotational vibration stimuli into the mechanical mounting; collecting vibration data with the accelerometer for use in determining the rotational vibration index for the mechanical mounting environment; providing a rotational vibration index for the drive species for comparison with the determined rotational vibration index; and comparing the rotational vibration index calculated for the mechanical mounting environment with the rotational vibration index of the drive species to relate the rotational vibration stimuli of the mechanical mounting environment to the performance of the sample disc drive.

Abstract: Apparatus and method for writing servo data to a disc of a disc drive. A disc pack comprising a disc and a spindle motor is mounted in a stationary disc servo track writing (STW) fixture, which maintains the disc in a nonrotating, stationary relation while rotating a servo write head around a circumference of the disc to write the servo data to the disc. Once the servo data are written and verified, the disc is removed from the STW fixture and installed into a disc drive. The STW fixture preferably comprises a stationary base portion, top and bottom clamp members which extend from the base portion to hold the disc in the nonrotating, fixed relation, and a rotatable enclosure, adjacent the base portion, which supports the servo write head and rotates with respect to the base portion using air bearings.

Abstract: A snubber for a plurality of discs in a disc drive has a pivoting body with extending portions having angled surfaces that abuttingly engage the discs in a closed position of the pivoting body, the angled surfaces alternatively clearingly disengaging the discs in an open position of the pivoting body. A spring member biases the pivoting body to the closed position, and a solenoid when electrically energized imparts an opposing rotational force to urge the pivoting body to the open position. In the closed position the angled surfaces provide a two-point contact in support of each disc, the surfaces supporting the disc on each side of the disc to provide a fixed support of the disc at the edge thereof.

Abstract: Apparatus and method for writing servo information in a head disc assembly (HDA) comprising a head, a disc and a spindle motor for rotating the disc. The servo information is written by the head to servo fields on the disc. A positioning system positions the head relative to the disc and a control circuit controls the positioning of the positioning system as well as the rotational speed of the spindle motor. An electro-mechanical transducer outputs a signal indicative of vibratory response of the HDA as the disc is rotated and a computer is provided which instructs the control circuit to rotate the spindle motor at each of a plurality of rotational speeds while characterizing the vibratory response of the HDA using the signal from the transducer for each of the rotational speeds. An optimal rotational speed is thereafter selected and used to write the servo information, the optimal rotational speed minimizing variation in the placement of the servo information.