Abstract: According to one embodiment, a disk device includes a first actuator assembly and a second actuator assembly which are respectively supported by a first bearing unit and a second bearing unit to be rotatable about a support shaft. The first bearing unit includes a first sleeve and a ball bearing. The second bearing unit includes a second sleeve and a ball bearing. The first sleeve includes a first end surface opposed to the second sleeve and an annular first step projecting from the first end surface, and the second sleeve includes a second end surface opposed to the first step with a gap and an annular second step projecting from the second end surface. The second step is opposed to the first step and the first end surface with a gap.

Abstract: A hard disk drive includes multiple actuator assemblies, each of which includes a head-stack assembly (HSA) including an end-arm to which a single head-gimbal assembly (HGA) is coupled, where this end-arm is configured with a notch along one side and a triangular or quadrilateral-shaped through-hole at a root-side of the end-arm, and where the HSA further includes a plurality of other end- and inner-arms to each of which two HGAs are coupled and none of which have a through-hole near their root. The single-HGA end-arm may be further configured with an outer damper having a through-hole coincident with the end-arm through-hole, such that the through-hole of the end-arm is not covered by this damper, and an inner damper having no through-hole, such that the through-hole of the end-arm is covered by this damper. Gains are thereby better matched across all HGAs for problematic arm and system modes.

Abstract: According to one embodiment, a disk device includes a first actuator assembly on a support shaft via a first bearing unit, and a second actuator assembly on the support shaft via a second bearing unit. The first bearing unit includes a first shaft on the support shaft, a first sleeve fixed to the first actuator block, and a bearing between the first shaft and the first sleeve. The second bearing unit includes a second shaft on the support shaft, separated from the first shaft, a second sleeve fixed to the second actuator block, and a bearing between the second shaft and the second sleeve. One axial end of the first shaft faces one axial end of the second shaft.

Abstract: A disk apparatus includes recording disks and a first and a second actuator assembly that rotate about a support shaft and that each include: an actuator block; a wiring board having connection terminals and installed on an installation surface of the actuator block; and head assemblies each attached to the actuator block via an arm and each including a head and an interconnection member. The wiring board of each of the first and the second actuator assembly has a connection portion connected to one of the connection terminals and located adjacently to a boundary between the first and the second actuator assembly, and the connection portion of the first or the second actuator assembly is bent with respect to the installation surface.

Abstract: An actuator rotational limiter mechanism for a multiple disk-stack, shared actuator hard disk drive includes an actuator comb with a cam-lock feature and an actuator limiter with a rotatable cam-roller that is engagable with the cam-lock feature to temporarily hold in place the actuator comb. The cam-lock feature may be positioned at or near a middle location of a back arm of the actuator armature, where the actuator comb being held in place by the cam-roller corresponds to the head slider being positioned on a load/unload ramp between adjacent disk stacks.

Abstract: Disclosed is a flexure for a head/gimbal assembly suspension for a disk drive. The flexure comprises a metal base layer that includes two outrigger beams and a support island supported by a pair of beams extending from a flexure tongue. The flexure further comprises: a trace layer that is disposed over the base layer that includes a plurality of conductive traces, each conductive trace having a curved section that terminates in a trace termination pad; and a dielectric layer disposed between the trace and base layers including a portion underlying the trace termination pads and overlying the support island. The support island is supported by the pair of beams extending from the flexure tongue and is sized to fully support the trace termination pads of the conductive traces.

Abstract: A head-stack assembly. The head-stack assembly includes: a magnetic-recording head; a lead-suspension supporting the magnetic-recording head on an actuator arm; a metal plate coupled with the actuator arm; a resin layer disposed on the metal plate; a flexible-printed-circuit board disposed on the resin layer, and substantially perpendicularly connected to the lead-suspension; a arm-electronics module disposed on the flexible-printed-circuit board configured to shape a write-signal current waveform of a write signal to said magnetic-recording head; transmission lines disposed on the flexible-printed-circuit board configured to transmit the write signal to, and a read-back signal from, the lead-suspension; and, a single intermediate conductor layer that is disposed between the resin layer and the flexible-printed-circuit board, and having a planar shape substantially facing a bottom of the arm-electronics module and a bottom of the transmission lines.

Abstract: A variable capacitance device including at least one first fixed electrode and a second electrode free to move with respect to the fixed electrode, each electrode including a body and protuberances projecting from at least one face of the body. Each electrode is arranged such that the faces of each electrode provided with the protuberances are facing each other, the distance separating the two faces facing each other being greater than the sum of the heights of a protuberance from the fixed electrode and a protuberance from the mobile electrode. The electrodes are capable of moving with respect to each other in two parallel planes along at least one main direction.

Abstract: A method for making a dual actuator pivot, wherein the need for adhesive bonding is eliminated and assembly time is minimized. An upper sleeve assembly includes an upper and lower ball bearing press fitted therein and a lower sleeve assembly includes an upper ball bearing press fitted therein, the first and second sleeve assemblies being press fitted to a shaft having a ball bearing press fitted at the base of the shaft. A predetermined axial load that is tuned to select a desired resonance frequency for the first and second actuator bearing assemblies may be applied during the press fitting of the first and second sleeve assemblies. The shaft may be chilled to shrink the shaft. Alternatively, the components may be heated.

Abstract: A data storage device is provided having at least one disk rotated by a spindle motor and at least one actuator arm assembly rotatable in response to a voice coil motor about a pivot point for moving a magnetic head on an actuator arm for writing data onto the tracks of the disk and reading the data recorded on the tracks of the disk. The data storage device comprises a first plate, the spindle motor being secured to the first plate and a second plate secured to the first plate, the actuator arm assembly being secured to the second plate. A method for mounting at least one actuator assembly within a data storage device is also provided.

Abstract: A system and method for assessing and potentially correcting for non-translational motion in a resonance measurement apparatus is provided. The design measures the response of an article, such as an HGA assembly including a read/write head, as well as the excitation of a shaking device, such as a head resonance tester, and computes a correction factor using either two or three point measurement. The correction factor may be evaluated by subjecting the arrangement to further vibration at varying frequencies. Measurement of the shaking device may be accomplished using an accelerometer or by optical measurement using a light beam.

Abstract: A new fixture which is capable of holding an HSA throughout all processes is invented so that Quasi-Static Test can be done before swaging. Handling operations are reduced and rework is made much easier. The invention further provides a process for testing the HSA by means of the fixture.

Abstract: A magnetic disk unit has two actuators each rotating on a common rotary shaft. The two actuators are driven by a voice coil motor. The voice coil motor comprises: a magnetic circuit comprising a magnet provided for the two actuators on a common basis and two yokes, which are associated with the two actuators, respectively, said two yokes being disposed at both sides between which the magnet intervenes; and two coils provided for the two actuators, respectively.

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: Disclosed is a multiple rotary actuator assembly consisting of a plurality of modular actuators, wherein each modular actuator is mounted to and rotates independently about a common pivot shaft. Modular actuators consist of Integrated and Data arms, upon which multiple read/write transducers are mounted, for the recording and recovery of digital data. An integrated arm also contains a spiral conductor pattern that interacts with a multi-gap voice coil motor, to provide the necessary torque to rapidly position the modular actuator.

Abstract: A dual actuator pivot bearing system and method for making the same is disclosed, wherein the need for adhesive bonding is eliminated and assembly time is minimized. The dual actuator pivot includes a first and a second actuator bearing assembly that include an upper sleeve having an upper and lower ball bearing press fitted into the upper sleeve to form the first actuator bearing assembly and a lower sleeve having an upper ball bearing press fitted into the sleeve to form the second actuator bearing assembly, the first and second actuator bearing assemblies being press fitted to a shaft assembly comprising a shaft having a ball bearing press fitted at a shaft base. The first and second actuator bearing assemblies are press fitted using a predetermined axial load that is tuned to select a desired resonance frequency for the first and second actuator bearing assemblies.

Abstract: A multiple actuator disk drive is disclosed. The mechanical vibration in one actuator induced by motion in the second actuator is greatly reduced by providing an independent bearing shaft for each actuator. The bearing shafts are mounted substantially along the same geometric axis.

Abstract: A hard disk drive is made small in size, large in storage capacity and high in data reading/writing speed. Two actuator blocks (3) are fixed to a sleeve 16A of a first pivot and sleeve (16B) of a second pivot, respectively. Position of magnetic heads to be accessed to different magnetic disks are controlled independently by the actuator block 3 basis. Therefore, it is possible to distribute the reading/writing processing to the plurality of magnetic disks and perform these processing in parallel, to thereby increase the data reading/writing speed while increasing the storage capacity.

Abstract: A dramatic way to increase I/O performance, of a disk drive, is by the addition of another actuator to the disk drive. Dual-actuators allows the drive to overlap seeks, which produces a seamless stream of data to the host system by eliminating the breaks caused by conventional single actuators when they are repositioned.

Abstract: A magnetic recording disk device achieving higher speed, larger capacity and higher reliability. The disk device includes two or more actuator blocks that are individually and rotatably supported, and a device driver that causes a magnetic head of each of the actuator blocks to access its associated magnetic disk to arbitrarily perform read/write operations. The device driver is provided with a logic for driving, at an arbitrary RAID level, the magnetic heads of the respective actuator blocks and the magnetic disks accessed by the magnetic heads. By handling the magnetic head of each actuator block and the magnetic disk accessed by the magnetic head as one unit to implement a necessary function, a single magnetic disk device can be used as a simplified version equivalent to a RAID system.