Abstract: A method of manufacturing a disk drive is disclosed in which servo information is written in tracks on a disk surface, the track width performance of the associated read/write transducer is measured, the track width performance is analyzed and a data track pitch is established. Based on the data track pitch established, a track location formula for data tracks on the surface is defined. For a disk drive with a plurality of read/write transducer-media surface combinations, a track location formula for data tracks is established for each combination.

Abstract: A mass moves within a bore defined in a body. During normal operation the axis of the bore is approximately vertical, so that the mass rests at the bottom. A magnet is positioned adjacent the top of the bore and imparts an upwards force on the mass that is less than the downwards force on the mass upwards force on the mass that is less than the downwards force on the mass from gravity. A coil is positioned adjacent the bottom of the bore. When the body is dropped, or tilted beyond a critical angle from vertical, the force from the magnet causes the mass to move upwards in the bore. The upwards movement is sensed as a change in the coil's inductance.

Abstract: A hard disk drive assembly is electrically connected to a printed circuit board assembly motherboard using a connector on the hard disk drive assembly connected with a mating connector mounted on the motherboard. The hard disk drive assembly is secured to standoffs that allow sufficient space between the hard disk drive assembly and the motherboard for an integrated circuit package to be positioned between the hard disk drive assembly and the motherboard.

Abstract: Disclosed is a method to reduce external signal interference with signals in a computer disk storage system including a disk drive. An electrically conductive housing is provided for the disk drive to enclose and support within the housing analog circuitry, a motor for rotating media for the storage of information, and circuitry for converting analog signals to digital signals. Circuitry and conductors which carry analog signals are enclosed within the electrically conductive housing and signal conversion circuitry is provided within the housing to convert analog signals into digital signals before transmission to the exterior of the housing.

Abstract: A method of manufacturing a disk drive which includes a disk having first and second magnetic surfaces and first and second read/write transducers for writing information on and reading information from the magnetic surfaces. The method includes determining a track width performance characteristic to be measured for the read/write transducers, establishing ranges of values for the performance characteristic to define a plurality of performance groups. The performance characteristic is measured for a plurality of read/write transducers from which the first and second read/write transducers for the disk drive are to be selected and the read/write transducers are segregated into groups based on the performance characteristic value falling within the range of the group. The disk drive is assembled using read/write transducers from only one of the groups. The measurement of the performance characteristic is accomplished either electrically or optically.

Abstract: A method for operating a disk drive apparatus in the Idle Mode reduces power consumption while meeting non-operating shock and vibration specifications. This is achieved by operating the disk drive apparatus with the head in the loaded state with the disk rotating at a first rotational speed, unloading the head, and in Idle Mode, rotating the disk at a second rotational speed lower than the first rotational speed, with the electronics depowered.

Abstract: An acceleration sensing device senses the acceleration of a computer such that the computer is subject to zero support force (i.e., is in a free fall), and a control microprocessor of the disk drive unit determines that such state lasts for longer than a certain minimum of time. Upon these conditions being met, the control microprocessor signals the removal of the heads from the disk to park the heads.

Abstract: In accordance with this invention, an air bearing slider has a mounting side which has a relieved portion formed by a stepped-contour or a tapered contour. The stepped-contour includes an adherent surface adjacent the rear face of the air bearing slider and a notch surface adjacent the front face of the air bearing slider. The notch surface is closer to the air bearing surface than the adherent surface. The tapered contour includes an adherent surface adjacent the rear face and a taper surface adjacent the front face such that the taper surface is at an angle to the adherent surface. The clearance provided by the relieved portion eliminates interference between the air bearing slider and the load beam surround portions which support the air bearing slider. Depth of the relieved portion of the air bearing slider can be altered easily during grinding for customized multiple drive designs without major retooling effort.

Abstract: In accordance with this invention, an air bearing slider has a mounting side which has a relieved portion formed by a stepped-contour or a tapered contour. The stepped-contour includes an adherent surface adjacent the rear face of the air bearing slider and a notch surface adjacent the front face of the air bearing slider. The notch surface is closer to the air bearing surface than the adherent surface. The tapered contour includes an adherent surface adjacent the rear face and a taper surface adjacent the front face such that the taper surface is at an angle to the adherent surface. The clearance provided by the relieved portion eliminates interference between the air bearing slider and the load beam surround portions which support the air bearing slider. Depth of the relieved portion of the air bearing slider can be altered easily during grinding for customized multiple drive designs without major retooling effort.

Abstract: An enhanced method and system for unloading magnetic heads are disclosed. The system limits the maximum and minimum speed of the actuator while unloading the heads during a power failure. A BEMF control circuit monitors the velocity of the actuator using the BEMF of the actuator as a gauge of the velocity. The BEMF control circuit uses a sense resistor to remove the inherent resistive component of the actuator from its BEMF measurement. If the velocity of the actuator increases above a safe level the BEMF control circuit decreases actuator current to prevent further acceleration. If the velocity of the actuator decreases below a safe level the BEMF control circuit increases the actuator current to accelerate the actuator to a safe level.

Abstract: A disk drive with a drive motor having a spindle rotatable around an axis of rotation, one or more disks mounted on the spindle separated by annular spacers which have a radial dimension selected to maintain flatness of the disks, an annular ring dimensioned to distribute force evenly to the disks engaging the last mounted disk, a flat annular spring clamp for applying force uniformly to the annular ring, and a retaining member to hold the annular spring clamp in place.

Abstract: An adaptive servo system for a disk drive compensates for a track being off center or distorted by analyzing the spectral content of the radial variation of the centerline of a track relative to a rotation axis, generating multiple component signals having frequencies that are harmonics of the rotation frequency, and combining the component signals in a positioning signal for an actuator. Analyzing the spectral content of the radial variation can be accomplished by a discrete Fourier transform of a position error signal while generating a correction signal that cancels all or part of previously determined components of the position error signal. The system converges to generating a periodic signal that compensates for multiple harmonics in the radial variation in the position of the track.