Abstract: A disk drive motor spindle hub rotatable about a central shaft has a ceramic hub flange attached to a cylindrical hub portion. The ceramic hub flange has a peripherally raised area on which a first disc rests. Additional discs and spacers are alternatively stacked on top of the first disc. The spacers are made of ceramic material with an inner relieved portion. A ceramic clamp washer with peripherally raised area and an inner relieved portion is stacked on top of the first disc. A ceramic clamp washer with a peripherally raised area and an inner relieved portion and a clamp spring in cooperation with the hub flange apply force to hold the first disc and additional discs in place. The clamp force is applied away from the inner diameter of the discs while portions near the inner diameter of the discs are isolated from the hub flange, spacer and the clamp washer.

Abstract: A support assembly for supporting a magnetic circuit of a disc drive voice coil motor, the support assembly suppressing the excitation of mechanical resonances in the drive. The disc drive includes a disc and an actuator assembly adjacent the disc, the actuator assembly having a coil of a voice coil motor to which current is applied in order to position a head of the actuator assembly relative to the surface of the disc. The voice coil motor further includes a magnetic circuit comprising a pair of permanent magnets and corresponding magnetically permeable pole pieces disposed above and below the coil. The support assembly suspends the magnetic circuit between a base deck and a top cover of the disc drive and allows cantilevered movement of the magnetic circuit in response to the acceleration of the coil as a result of current being applied to the coil.

Abstract: A disc drive including a dual disc clamp for clamping a number of hard discs within a disc drive is disclosed. The clamp is comprised of a top circular clamp member in contact with a bottom circular clamp member, with the clamp members having the same physical shape and area. The bottom clamp member has number of holes formed therein which reduce the disc distortion. The top clamp member has a concave upper surface, while the bottom clamp member has a convex upper surface. The clamp holds the discs in place through pressure provided by a plurality of screws which are passed through holes in the clamp members. The disc drive also includes a spindle motor to which the dual disc clamp is connected. The spindle motor provides a greater torque constant, thereby allowing lower start and run current.

Abstract: A data storage disc having an improved landing zone for supporting a head gimbal assembly for takeoff and landing. The improved landing zone having a landing surface formed of a patterned surface structure. The patterned surface structure including contact surfaces formed generally flush with a disc surface and depressions formed into the disc surface at predefined spaced location and extending below the disc surface. The patterned surface structure reducing stiction for "takeoff" of a slider from the disc surface and reducing interference of the slider and disc surface while flying over a transition zone at the edge of the data zone and landing zone.

Abstract: A disc head slider (36) includes a slider body with leading, trailing, inside and outside slider edges (50,52,54,56) and a slider center line (58) extending from the leading slider edge (50) to the trailing slider edge (52). First and second raised side rails (60,62) are formed in the slider body and each include an inside rail edge (108), an outside rail edge (110), a leading rail edge (50) and a trailing rail edge (112). The first and second raised side rails (60,62) form first and second bearing surfaces (70,72), respectively, which terminate prior to the trailing slider edge (52). A raised center rail (64) extends along the slider center line (58) and between the first and second raised rails (60,62). First and second cavities (80a,80b) are positioned between the raised center rail (64) and the first and second raised rails (60,62), respectively.

Abstract: A bearing having two surfaces (60, 72) rotatable with respect to each other, a lubrication medium located in a gap between the tow surfaces during rotation of the bearing and a sinusoidal groove pattern (20) formed on one of the tow surfaces to distribute the lubrication medium over the surface of the bearing and create a pressure distribution in the bearing to create a stiff hydrodynamic bearing.

Abstract: A rotary actuator for disk drives includes a carriage rotatable on a vertical axis, and multiple transducing head suspensions extended horizontally away from the carriage in cantilever fashion. Data reading and writing circuitry includes an electrical circuit package mounted at the carriage, and multiple flexible printed circuits extending horizontally away from the circuit package, each for electrical coupling to one of the transducing heads. A series of slots, formed through the circuit package along one edge, support the flexible printed circuits to achieve an electrical and mechanical coupling that orients the flexible printed circuits with their major planes horizontal throughout their respective lengths, avoiding any twists of the flexible circuitry while providing improved damping and electrical performance. Alternative connecting structures, in lieu of the slots, include rigid rails on one or both sides of each flexible printed circuit, and bendable tabs incorporated into the printed circuits.

Abstract: Apparatus and method for enhancing the convective cooling of a voice coil motor (VCM) of a disc drive. A portion of an air flow established by the rotation of a disc of the disc drive is diverted from the disc and is directed through a channel to the VCM. In one embodiment, an air foil is provided to support first and second magnetic paths of the VCM, the air foil having a shroud surface adjacent portions of the circumference of the disc and a diverter surface angularly extending from the shroud surface, the diverter surface diverting the air to the VCM. Alternatively, a base deck of the disc drive is provided with a shroud circumferentially adjacent portions of the disc and the channel extends through the shroud to direct the air from the disc to the VCM.

Abstract: The spindle motor is integrated with the disc by incorporating one of the poles or coils of the motor with a region on the disc, and the remaining portion of the motor being distributed over an internal surface or surfaces of the housing for the disc, or over the edge of an adjacent disc. By activating the portion of the motor which is supported from the disc housing, the disc can be rotationally driven. The motor poles may be either deposited or etched on the disc, or separately formed and attached to the disc housing. The result is a substantially smaller height disc drive, achieved with a much reduced cost.

Abstract: A disc drive data storage system according to the present invention includes a housing, a central axis, a stationary member which is fixed with respect to the housing and coaxial with the central axis, and a rotatable member which is rotatable about the central axis with respect to the stationary member. A stator is fixed with respect to the housing. A rotor is supported by the rotatable member and is magnetically coupled to the stator. At least one data storage disc is attached to and is coaxial with the rotatable member. A hydro bearing interconnects the stationary member and the rotatable member and includes a blend of a base fluid having a viscosity index of at least 110, an anti-oxidant additive, anti-corrosion additive and an anti-wear additive, which are effective for resisting catalytic degradation in the hydro bearing.

Abstract: The present invention pertains to an apparatus and method for determining at most four error locations of RS encoded data read from a storage medium. The error location polynomial solver includes a controller, a multiplexer, storage registers, a data flow control unit, and various GF(256) arithmetic units. The GF(256) arithmetic units include GF(256) multiply unit, a GF(256) logarithmic ROM, a GF(256) anti-logarithmic ROM, a GF(256) square root unit, a GF(256) quadratic root finder, and a specialized integer division unit. The controller directs the operation of each of these components to perform one or more equation solver procedures that determine the appropriate number of roots. In an embodiment of the present invention, the controller is implemented as a state machine. The controller receives four coefficients representing an error location polynomial. The degree of the error location polynomial is determined in order for the controller to execute an appropriate equation solver procedure.

Abstract: A tester for use in detecting asperities in a disc surface of a storage system includes a load arm having a proximal end and a distal end. The distal end of the load arm is positioned adjacent the disc surface. A slider is carried on the distal end of the load arm adjacent the disc surface. A thermal sensor is coupled to the slider and provides an electrical output in response to a thermal input due to interaction between the thermal sensor and asperity on the disc surface. Detection circuitry coupled to the thermal sensor detects the electrical output from the thermal sensor and responsively provides a detection output indicating the occurrence of an asperity on the disc surface.

Abstract: A voice coil driven positioner is provided for positioning the magnetic head of a tape drive relative to the tape of a removable tape cartridge. The head positioner includes a low-mass carriage that supports the head on one end and the voice coil on an opposed second end. A low friction guide mechanism guides the carriage along a precision movement path that carries the head across tracks of a supplied multi-track tape and simultaneously carries the voice coil through a flux field generated by a stator. A movable magnet is attached to the carriage and located within the hollow of the voice coil for reciprocating into a hollow passageway of the stator together with reciprocation of the voice coil into another hollow of the stator. A flux detector is attached to the stator and located compactly within the hollow passageway of the stator for detecting the position of the magnet.

Abstract: A base plate is used to attach the head/gimbal assembly of a disc drive to an actuator arm. The base plate has a boss which fits into an opening in the actuator arm. In one embodiment, one of the inner surface of the opening in the actuator arm and the outer surface of the boss is constructed of polymer, and the other is constructed of metal. The base plate is secured to the actuator arm by swaging the raised portion of the base plate to the opening in the actuator arm. During swaging, the layer of polymer material yields to conform to the metal surface, thereby providing a swage connection with superior holding friction and retention torque. In another embodiment, the boss includes a plurality of raised portions defining a cylinder having a relaxed outer diameter greater than the inner diameter of the opening in the actuator arm.

Abstract: A disc drive data recovery system for recovering data from a magnetic disc having asperities is disclosed. The data recovery system includes a magnetoresistive head for reading magnetically encoded data from the magnetic disc and providing in response a signal indicative of the magnetically encoded data. Contact between the magnetoresistive head and an asperity corrupts the signal such that the signal contains thermal asperity noise. The data recovery system includes an asperity recovery filter coupled to the magnetoresistive head for receiving the signal from the magnetoresistive head and reducing the thermal asperity noise in the signal.

Abstract: A single-sided electronic connector for assembly to a printed circuit board assembly (PCBA) includes a connector housing having a pin supporting wall extending the width thereof, a plurality of conductive pins extending from an outboard side of the wall, a plurality of soldertails corresponding to the conductive pins extending from an inboard side of the wall, and a plurality of gripper arms which extend from an inboard side of the housing for receiving and securing an edge of the PCBA therein through an interference fit such that the soldertails engage only one side of the PCBA. Each gripper arm defines a slot having crush ribs into which the edge of the PCBA is inserted. A pair of mounting ears extend from a respective pair of gripper arms, and are configured to receive a mounting screw therethrough for attaching the electronic connector to a support structure.

Abstract: A system is disclosed for detecting local surface discontinuities in magnetic data storage disks. The system includes a spindle that rotatably supports a magnetic disk being tested. An interferometer generates a laser beam which is guided through an optics assembly supported above the magnetic disk, for linear movement radially of the disk. The combined radial and linear movement causes the laser beam to trace a spiral scanning path on the disk surface. The disk surface scatters the laser energy, a portion of which is returned to the interferometer and caused to interfere with a reference beam. The resulting interference intensity fluctuates in response to changes in the optical path length, thus measuring topographies of the discontinuities. A discontinuity recognition triggering pulse can be positioned in time with respect to indexing pulses, to identify the location of the associated discontinuity radially and angularly of the disk.

Abstract: A slider for attachment to a flexure of a disc drive system includes a slider body, a transducing head formed on the trailing edge of the slider body, and a microactuator formed on the leading edge of the slider body. The microactuator engages the flexure to rotate the transducing head in response to control signals applied to the microactuator. The slider is applicable to achieve fine positioning of the transducing head in a disc drive having an actuator arm supporting the flexure and a motor operable to move the actuator relative to a disc to coarsely position the transducing head. The microactuator and the transducing head may be formed by thin film deposition.

Abstract: An apparatus comprising a magnetic head suspension assembly (10) comprised of a rectangular portion (12), load beam (14) and flexure (16) fabricated from a silicon structure using the etching techniques of the integrated circuit fabrication industry. The magnetic head suspension assembly (10) has electrical leads (23) to a slider, a pre-amp circuit (25) and a microactuator (27) fabricated directly thereon. A system of providing a loading force passing to slider (50) comprises either a tapered base plate (40) adapted to be held by a horizontally oriented actuator arm or an actuator arm (60) having at least one angled receiving surface (62,64) for attachment to said suspension assembly.

Abstract: The coercivity of a magnetic recording medium is increased without any substantial change in magnetic remanence by depositing a fresh non-magnetic sub-underlayer on an underlayer or composite underlayer comprising a plurality of sub-underlayers, and immediately depositing a magnetic layer on the fresh sub-underlayer. In an embodiment of the present invention, a fresh chromium sub-underlayer having a thickness of about 55 .ANG. to about 135 .ANG. is sputter deposited on a chromium underlayer in the magnetic layer deposition chamber, and a cobalt magnetic layer deposited on and within 1.2 seconds after depositing the fresh sub-underlayer.