Abstract: An apparatus joins bonding pads of a slider and lead pads of lead wires in a head gimbals assembly to improve efficiency, downsizing, and maintenance of solder-ball disposing devices, and solder-ball reflow devices for reflowing solder balls. The solder-ball disposing apparatus discharges solder balls from solder-ball discharging holes of a solder-ball feeder unit which are evacuated by a suction pad. An environmental space and an inert-gas supply portion for forming inactive atmosphere are formed on a table to eliminate an inert-gas supply unit from an optical unit, so that converged laser beams are directly radiated onto the solder balls.

Abstract: Disk substrates are polished in a process which uses a single load of the disks to a polishing apparatus and a single polishing slurry. Preferably, the process varies at least one polishing parameter at multiple stages to achieve both a reasonable rate of removal during one stage and a smooth finished surface during another stage. Preferably, a fine grit cerium oxide slurry is used, along with a polishing pad having surface characteristics intermediate those of relatively hard pads typically used for material removal, and of relatively soft pads typically used for fine finishing. The polisher operates at high pressure and speed during a material removal stage, and then reduces speed and pressure during a finishing stage to achieve a suitable surface finish, without removing and cleaning disks between the two stages.

Abstract: To provide a method of starting a data storage unit which allows a computer system to be used as early as possible. The present invention relates to a method for starting up a computer system having a data storage unit equipped with an actuator arm which supports a flexible cable. The method allows a command from the host computer to be processed before generation of corrected tension data for the flexible cable. The method includes the steps of turning on power; executing a start operation, excluding generation of corrected tension data of the flexible cable; causing an access command from a host computer to be in an executable state, following the step of executing a start operation; and executing generation of corrected tension data of the flexible cable, following the step of causing an access command from a host computer to be in an executable state.

Abstract: A joining technique and design for welding hard to weld elements of a disk drive suspension machines or coins the parts to be welded at their weld interface. A small pocket is formed at the weld interface to let evaporated material gases escape during welding and reduce gas bubble trapping in the weld nugget. For laser welding, a pocket is formed in thick parts to control the welded web thickness for fast melting and thorough mixing of top and bottom materials. For resistance spot welding, it may be necessary to form pockets in both materials on the electrode contact side to reduce material thickness. This technique provides a weld interface design that solves joint reliability and dynamic variation problems. This technique can be used to attach aluminum-to-aluminum or other materials that are difficult to weld due to porous welds, and to improve weld quality of both spot and seam welds.

Abstract: A method and apparatus for use with a rotating storage device. The rotating storage device includes a storage medium driven to rotate, a head for reading and writing information on the storage medium and a ramped loading mechanism in which the head is stored. In accordance with the method of the present invention, the head is loaded from the ramped loading mechanism onto the storage medium. Next, location information stored in the storage medium via the head is read. A location of the head is then retained for a predetermined period above a track of a region other than a valid storage region of the storage medium after successfully reading the location information.

Abstract: A suspension arm (300) of a disk storage device has an elastic portion (310) with thickness d1 and a rigid portion (320) with thickness d2. At the free end of the suspension arm, a slider (325) is mounted on the suspension arm. The bottom surface of the slider has a distance FH to a top surface of a hard disk (329). The suspension arm particularly comprises a heating element (330) disposed on the suspension arm. An electric current Ic flowing through electrical supply wires (350) causes the temperature of the suspension arm locally to rise and therefore its spring constant to decrease. Together with the force Fa resulting from the air cushion effect of the slider a new equilibrium flying height FH is stabilized.

Abstract: A method is provided for forming a body for a hard disk carriage assembly from polyphenylene sulfide 40% glass fill. An injection mold is heated to approximately 130° C.; then a volume of polyphenylene sulfide 40% glass fill is injected into the mold to form the body of the carriage assembly. The polyphenylene sulfide 40% glass fill is then cooled within the mold for approximately 45 seconds before the body is ejected from the mold cavity. The body is then heated to approximately 130° C. for at least 2 hours in a post-bake operation.

Abstract: A scheme for ultrafast magnetization reversal in an in-plane magnetized layer (3) is disclosed. For that, an external magnetic field {right arrow over (H)}ex is applied such that the magnetization {right arrow over (M)} precesses around the external magnetic field {right arrow over (H)}ex and the external magnetic field {right arrow over (H)}ex is maintained until the precession suffices to effect the magnetization reversal. The external magnetic field {right arrow over (H)}ex is applied approximately perpendicular to the magnetization {right arrow over (M)}.

Abstract: A parallel read/write circuit for use with a plurality of transducer head assemblies and method of operation thereof. The parallel read/write circuit includes a parallel read/write cache, e.g., a bidirectional parallel-serial converter buffer in one advantageous embodiment. A byte-to-bit disassembler, coupled to the parallel read/write cache, receives parallel data from the parallel read/write cache and transmits each bit of the parallel data to a separate transducer head assembly, where each bit of the parallel data is written onto a different disk surface of a recording medium at substantially the same time. In an advantageous embodiment, the byte-to-bit disassembler is a parallel in/parallel out shift register.

Abstract: An apparatus and method for adjusting balance in a disk drive, and a method for assembling a disk drive, enables the modification of dynamic balance reliably and efficiently. The apparatus adjusts balance in a hard disk drive having disks and a spindle which are assembled in a base. The acceleration to be applied from an actuator is made to act on the top end of the spindle through a holder plate in one accelerator, while the acceleration to be applied from an actuator is made to act on the base end of the spindle through the base in another accelerator.

Abstract: A disk drive damper avoids matching a frequency band of a sound frequency peak generated by the rotation of a spindle motor and a resonant frequency of the damper. The damper is attached to a disk drive apparatus and enabled to repress vibration. The damper includes a flat base portion and wall-thickness portions that are thicker than the flat base portion. The damper is varied in shape more freely than conventional flat dampers. Consequently, the resonant frequency of the damper can be adjusted more freely than ever.

Abstract: A disk drive pivot assembly design has a shaft that supports two actuators. The pivot assembly design compensates for the tilting of the actuators due to shaft bending during seek operations. Two types of bearings of differing stiffness are used to achieve improved performance. The axially innermost bearings are stiffer than the axially outermost bearings, which are relatively compliant. By having two different bearing stiffnesses, the boundary conditions of the pivot assembly are adjustable and can compensate for shaft bending, which is greatest near the center of the pivot assembly.

Abstract: A breather filter for a hard disk drive is attached to a hole provided in the cover of the disk drive. The breather filter has a first sheet that forms a diffusing tube at a position corresponding to the hole provided in the cover of the disk drive. The filter also has a second sheet forming an opening at a position corresponding to the diffusing tube of the first sheet. A third sheet of the filter has an adsorbent layer at a position corresponding to the opening in the second sheet. Finally, a fourth sheet, including a filter layer, covers the adsorbent layer of the third sheet and is stacked with each of the sheets.

Abstract: An in-situ (result-directed/predictive) MR stripe height calibration method capable of operating on the fly during lapping operation. The method involves utilization of an interval sampling technique, which provides a high number of data points. The data provided are filtered and averaged at each kerf location to provide a much higher calibration accuracy than previously available. The primary advantage is to create an accurate relationship between MR element resistance and its stripe height while the MR element is being lapped. The method thus provides the ability to target either resistance or stripe height or a combination of both during the lapping process. Finally, the system is completely self-contained and does not required wafer data.

Abstract: A disk drive utilizes a slider that is designed to fly very high or well above the surface of the disk when loading onto the disk and until a reading or writing operation requires the head to go to a relatively low-flying position with respect to the disk. Thus, the slider has two or more altitudes at which it flies depending on the operating conditions of the disk drive. The different altitudes of the slider are achieved by adjusting three primary variables: the rotational speed of the disk, selecting the radial position of the slider/actuator arm, and by the gram load. Other factors that may be used to tune this performance include pitch static attitude, pitch stiffness, and air bearing surface design.

Abstract: A lubricant retention design for a fluid dynamic bearing design in a spindle motor utilizes a labyrinth gap that is formed between the sleeve and the shaft of the bearing. The gap is used in conjunction with a barrier film to impede the flow of lubricant into the lateral and axial vent holes during non-operational vibration, such as shipping and handling of the end product. In another version, a plug is located in the lateral vent hole. The plug has a very small passage that permits air to pass therethrough for atmospheric pressure equalization, but prevents the escape of lubricant into the vent holes. Alternatively, the plug may be formed from a non-wettable material such as porous foam or sintered material and provided with a larger opening. Yet another solution utilizes a combination of both the labyrinth and plug designs.

Abstract: A slider and suspension of a hard disk drive are joined with a low modulus epoxy adhesive. The slider and suspension are set in a bonding jig while they are moving from process to process or subjected to a thermosetting treatment in a controlled temperature chamber. The slider and suspension must be kept bound together with the bonding jig until the adhesive is cured through a thermal treatment. The low modulus epoxy adhesive is cured with heat from a laser beam. In addition, a resistance value of the head disposed at the slider is measured so as to monitor the temperature of the head, thereby deciding both output and irradiation time of the laser beam for obtaining a desired strength of the bond within a predetermined temperature range.

Abstract: A method and apparatus for detecting an abnormal fly height of a magnetic head. The method includes reproducing a servo signal recorded on a magnetic disk in advance by the magnetic head when a write operation for writing data on the magnetic disk by the magnetic head is initiated. Next, the gain of the servo signal based on the head part of the servo signal reproduced by the magnetic head is determined. The gain of the servo signal is then compared with a reference value to detect an abnormal fly height of the magnetic head. In an advantageous embodiment, the reference value is the gain of a servo signal determined when the fly height of the magnetic head is normal. Alternatively, in other advantageous embodiments, the reference value is based on the gain of a previous servo signal.

Abstract: A shaper for an ion beam gun has a plate with a non-symmetrical profile including notches and tabs. The shaper is mounted to the surface of an ion beam grid having an array of holes. The shaper is oriented radially on the grid and covers some of the holes in the grid. The grid is mounted to an ion beam gun above a specimen that is rotated beneath the ion beam gun. The ion beam is filtered into smaller ion beamlets by the grid. The ion beamlets permeate the holes in the grid that are not covered by the shaper. The ion beamlets reach the specimen to etch it more uniformly than a grid that does not have a shaper. The shaper may be further optimized for a particular grid via a trial-and-error process to even further refine the uniformity of etching depth.

Abstract: A lapping process fixture has a base with a mounting surface and a membrane on the mounting surface for supporting a workpiece. The membrane is bonded to the mounting surface and has adhesive on its outer surface such that the workpiece adheres to it. The membrane extends across and seals an opening to a cavity inside the base. The cavity is filled with fluid that may be sealed or externally pressurized through ports in the base. The fixture restrains the workpiece to minimize distortion of its surface during processing. The workpiece is restrained from normal-directed movement by fluidic pressure such that the normal force is uniformly distributed across the surface area of the workpiece. The external adhesive on the membrane restrains the workpiece from tangential movement.