An approach to a reduced-head hard disk drive (HDD) involves a load/unload (LUL) ramp subsystem that includes a ramp assembly that includes a rotatable latch link configured for mechanical interaction with a head-stack assembly (HSA) and a LUL ramp coupled with the latch link, configured such that in response to a force applied to the latch link by the HSA, the latch link rotates which disengages a magnetic latch and drives the LUL ramp to rotate into an operational state disengaged from any recording disk of a multiple-disk stack. The subsystem may further include a motor configured to drive rotation of a lead screw to which the ramp assembly is attached, to drive vertical translation of the ramp assembly, thereby providing for loading the vertically-translatable HSA onto and off of each of the disks of the disk stack.

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.

According to one embodiment, a magnetic disk includes a disk, first and second heads which write data to the disk and read data from the disk, a first actuator includes the first head, a second actuator includes the second head, first and second controllers which control the first head, the second head, the first actuator and the second actuator, an auxiliary power supply which supplies power when power from a power supply is shut off, and a power supply detection unit which makes power supplied from the auxiliary power supply to the first controller higher than the power supplied from the auxiliary power supply to the second controller when shutoff of power from the power supply is detected.

According to one embodiment, a disk device includes a plurality of disk-shaped recording media, a first actuator assembly supported by a support shaft, a second actuator assembly supported by the support shaft and spaced from the first actuator assembly, a flexible printed wiring board includes a base portion, a first relay portion extending from the base portion and connected to the first actuator assembly, and a second relay portion extending from the base portion and connected to the second actuator assembly, a support member fixed to the base portion of the flexible printed wiring board, and a reinforcing member provided in the base portion in the vicinity of the first relay portion and the second relay portion.

A recording surface of a magnetic disk is divided into first and second zones. A first head of a first actuator arm assembly reads from and/or writes to the first zone exclusively. A second head of a second actuator arm assembly reads from and/or writes to the second zone exclusively. The first and second head are capable of simultaneously reading from and writing to the recording surface.

According to one embodiment, a disk device comprises a plurality of rotatable magnetic disks, a first actuator assembly, and a second actuator assembly. A slit provided in each of arms of the first actuator assembly is provided to be offset in a direction spaced away from a border plane between actuator assemblies with respect to a center of the arm in its thickness direction. A connection end portion of a wiring member is partially located in the slit, such as to be offset in a direction spaced away from the border plane, and disposed on a wiring board, and joined to the wiring board.

Dual and triple PMR writers are disclosed wherein the number of writer pads required to energize the selected PMR writer is minimized to three or four, respectively, with a coil configuration wherein separate top coils are connected by separate interconnects or side taps to separate bottom coils. Either top coils or bottom coils may be linked to a common W pad. Alternatively, there may be one bottom coil that allows all output current to flow to a common W pad. Coils may have a pancake or helical shape. In dual PMR writer embodiments, there may be one or two dynamic fly height heater coils. Magnetic performance in the selected writer of a dual PMR writer is similar to that of a single PMR writer with regard to erase width in AC mode (EWAC), Hy field, trailing and side shield return fields, down-track and cross-track gradient.

A data storage device is disclosed comprising a first disk surface, a first actuator arm, a first head connected to a distal end of the first actuator arm, an actuator, and a first coupler configured to couple the first actuator arm to the actuator. The first coupler is actuated in order to couple the first actuator arm to the actuator during at least part of a seek interval, and while the first actuator arm is coupled to the actuator, the actuator is moved in order to seek the first head over the first disk surface.

A hard disk comb includes: a main body including a groove; and an arm joined to the main body. A part of the arm is disposed inside the groove, and an opening edge of the groove is joined to an upper surface of the arm.

A disk device includes a magnetic disk having a data non-recording region, and a data recording region inside the data non-recording region, a plurality of heads configured to read and write information from and onto the magnetic disk, and a plurality of arms supporting the heads, the arms being rotatable to move the heads from a parked position to a desired data recording position above or below the magnetic disk. Each of the arms comprises an overlapping region that overlaps the data recording region of the magnetic disk in a thickness direction of the magnetic disk when the heads are at the parked position.