A data storage device is disclosed comprising a plurality of disk surfaces, a first plurality of heads actuated over a first subset of the disk surfaces by a first actuator, and a second plurality of heads actuated over a second subset of the disk surfaces by a second actuator. A first access command is executed using the first actuator and a second access command is executed using the second actuator. When the first access command finishes before the second access command finishes, a third access command is selected to execute using the first actuator based on a time remaining (To2) to finish the second access command, and at least part of the second access command is executed while concurrently executing at least part of the third access command during To2.

There is provided a bearing device including: a tubular sleeve; a shaft held inside the sleeve; and a first bearing, a second bearing, a third bearing, and a fourth bearing, rotatably holding the shaft with respect to the sleeve and arranged in this order in an axial direction. An outer circumferential surface of an outer ring of each of the first to fourth bearings is fixed to an inner circumferential surface of the sleeve, a gap is provided between inner circumferential surfaces of inner rings of the second and third bearings and the shaft, and a spring applying a constant pre-load is provided between the inner rings of the second and third bearings.

According to one embodiment, a disk device includes a housing with a bottom wall, magnetic disks supported on a hub of a motor, a printed circuit board provided on an outer surface of the bottom wall, and a wiring board attached on the outer surface of the bottom wall. The bottom wall includes a recess formed in the outer surface, a step located on border between the outer surface and the recess, and through holes opened to the recess. The wiring board includes one end portion disposed in the recess and connection pads on the one end portion, connected to lead wires of a coil. An adhesive is filled into the recess and the through holes, and covers the one end and a solder joint and seals the through holes.

A suspension assembly includes a baseplate having an upper surface and a lower surface opposite the upper surface, a load beam mounted to the baseplate, a cylindrical hub extending from the upper surface, wherein the cylindrical hub comprises an inner surface that defines a swage hole extending through the baseplate, and a plurality of dimples protruding from the upper surface of the baseplate, wherein each of the dimples includes a rounded side protruding from the upper surface of the baseplate and terminating in an apex. The apexes of the dimples define a contact plane for engaging with the lower surface of the actuator arm swaged to the cylindrical hub.

Systems and methods are disclosed for an actuator device or actuator control device to implement a low power savings mode. For example, a device can comprise an actuator arm including a first actuator and a second actuator, the second actuator configured to refine a movement of the actuator arm to a more precise position than use of merely the first actuator. A device can also comprise a control system configured to determine when the device is in an idle state and, when the device is in the idle state, disable the second actuator and perform a positional seek operation with the second actuator disabled. Power savings can occur from disabling the second actuator, which may also include disabling associated circuitry, such that it does not consume power or consumes a nominal (e.g., negligible or insignificant) amount of power during the associated seek operation.

A data storage device comprises a lead actuator that actuates a first read-write head over a first disk and a support actuator that actuates a second read-write head over a second disk. A spindle motor rotates the first and second disks. In response to an emergency power off (EPO) event, a processing device retracts and parks the actuators using an internal supply voltage generated from a back electromotive force (BEMF) voltage of the spindle motor, and brakes the spindle motor. The spindle motor is not braked until both the lead and support actuators have been retracted and parked.

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.

A disk device includes a plurality of magnetic disks, a plurality of magnetic heads, a first actuator assembly having a plurality of arms and a plurality of suspension assemblies for the magnetic heads and supported to be rotatable about a support shaft, a second actuator assembly having a plurality of arms and a plurality of suspension assemblies for the magnetic heads and supported to be rotatable about the support shaft, and a protective member formed from a material different from a material for the arms. The protective member is provided on a tip end portion of at least one of a first arm closest to the second actuator assembly among the of arms in the first actuator assembly and a second arm closest to the first actuator assembly among the arms in the second actuator assembly.

A data storage device includes a stack of data storage disks mounted on a spindle, a first arm and a second arm. The stack comprises a first plurality of upper disks and second plurality of lower disks. The first arm is movably attached to an actuator shaft, the first arm having a first head end that supports a first head, the first arm configured to move along a first portion of the actuator shaft to enable the first head to interact with data storage surfaces of the first plurality of upper disks. The second arm has a second head end that supports a second head, the second arm attached to and configured to move along a second portion of the actuator shaft, independently of the first arm, to enable the second head to interact with data storage surfaces of the second plurality of lower disks.

A data storage device, and systems thereof, including an actuator arm extending along an actuator axis and one or more rails extending along a rail axis. The rail axis is at an angle to the actuator arm and the actuator arm is movably attached to the one or more rails such that the actuator arm is restricted to linear motion along the one or more rails. Further, the device includes a linear motor positioned adjacent to the actuator arm and adapted to move the actuator arm. In one or more embodiments, the device includes a first actuator arm and a second actuator arm having the distal ends of each connected with at least one head located proximate the connection point.