Western Digital Technologies, Inc.

Hgst Netherlands, B.v.

Hitachi Global Storage Technologies Netherlands B.v.

Hajime Eguchi

Kouki Uefune

Kimihiko Sudo

Yuta Onobu

Kyosuke Yoshida

Toshio Takahashi

Takako Hayakawa

Takashi Kouno

Gaku Ikedo

Hiromitsu Masuda

Takenori Atsumi

Takehiko Eguchi

Hideaki Ito

Masakazu Sasaki

Eiji Soga

Seong-Hun Choe

Naoshi Mizumoto

Takehito Nagata

Shigenori Takada

A voice coil motor assembly (VCMA), such as for a hard disk drive, includes a low-density voice coil and a high-density coil stiffener disposed inside the coil of wire. The low-density voice coil, utilizing copper-clad aluminum or aluminum wire, is configured to increase the second coil torsion mode frequency of the VCMA, thereby bringing it closer to the second torsion mode frequency of the actuator arms. In conjunction, the high-density stiffener, utilizing steel or copper or zinc, is configured to increase the mass of the VCMA to compensate for the lower-density wire in regard to the center of mass of the VCMA about its axis of rotation. In viewing under customer box vibration conditions and in terms of position error signals (PES), a non-trivial peak in the PES spectrum due to the second coil torsion mode is largely eliminated, and the power of PES is reduced to about half.

Hard disk drive voice coil motor actuator with low-density wire coil and high-density coil stiffener

A data storage device may include an outer fine actuator group, an inner fine actuator group, and control circuitry comprising: a slew control voltage generator, a first switch, and a second switch. The control circuitry is configured to: generate a control signal; control the first switch to apply the control signal to a first fine actuator group for a first duration; control the first switch to apply the control signal to a second fine actuator group for a second duration, wherein each of the first and the second fine actuator groups comprises one of the inner or the outer fine actuator groups, and wherein the first and second fine actuator group are different; concurrently discharge the first fine actuator group during the second duration, based at least in part on controlling the second switch to couple the first fine actuator group to the slew control voltage generator.

Voltage slew control of fine actuators during discharge

The present disclosure generally relates to an interface connector in a tape embedded drive. The tape embedded drive has two long edges and two short edges. Within the tape embedded drive, there are numerous guide rollers, at least three feedthrough connectors, and two reels. The interface connector is located along one of the short edges and underneath one of the two reels. By placing the interface connector at that location, the tape embedded drive has sufficient real estate for all of the necessary reels, feedthrough connectors, and guide rollers while also ensuring stability of the tape embedded drive.

Interface connector for tape embedded drive

An electrical feed-through assembly includes electrically conductive pins having a top apex and a bottom apex, where the pins extend through at least a majority of an electrically non-conductive material. The top apexes, the bottom apexes, or both the top and bottom apexes of the pins have an electrically conductive connection pad material, such as a solder pad, coupled thereto. In variations, the top and/or bottom apexes may be slightly recessed from a corresponding surface of the non-conductive material, such that the connection pads fill the respective recesses; and/or the top and/or bottom apexes barely extend from a corresponding surface, such that the connection pads bulge out from the corresponding surface. Such a feed-through configuration may inhibit pin bending, in addition to enabling use of more types of connectors beyond pin-and-socket type connectors.

Electrical feed-through and connector configuration

In the context of a hard disk drive (HDD), an adhesive leak channel structural feature is positioned in an area at which an electrical feed-through is adhered with an adhesive to an enclosure base, where the leak channel feature inhibits the leakage of gas through the adhesive. Embodiments include providing the leak channel feature on the base and/or on the feed-through. Embodiments may further include application of an electrodeposition coating to the base in an area at which the adhesive is in contact.

Adhesive leak channel structure for hermetic sealing of a hard disk drive

Approaches to a rotary actuator assembly configured for use in a hard disk drive (HDD) include a voice coil interleaved between the pivot bearing and the actuator arm, providing a longer pivot-to-head dimension which reduces the radius of curvature of the arc in which the head slider travels over the disk for accessing portions of the disk. Reducing the arc radius of curvature reduces the maximum skew angles of the read-write head in association with the disk tracks. The width of the actuator arm can be widened to provide improved operating characteristics even in view of the longer pivot-to-head dimension.

Hard disk drive actuator assembly with interleaved voice coil motor

Approaches to improving head positioning accuracy in a hard disk drive, by suppressing airflow disturbances that would otherwise cause unwanted component vibration, include a voice coil motor having a sidewall spanning a gap between the VCM upper yoke and lower yoke. This VCM sidewall also serves as the inner wall of a bypass channel, for diverting airflow away from the actuator arm and associated components.

Hard disk drive bypass channel having a close-sided voice coil motor

Embodiments of the present invention help to suppress performance degradation in an actuator of a disk drive device when attaching a damping member to a single surface of an arm. According to one embodiment, in a HDD a damping member is attached to a single surface of an arm. A shape of an inner arm is asymmetric with the center position between disks. Specifically, the thickness from a center position between the disks to the damping material attaching surface is thinner than the thickness from a center position between the disks to an opposite surface of the damping member attaching surface. This suppresses deformation of the vibration mode in the case that the damping member is attached to the single surface of the arm.

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Fujisawa, Japan

Hajime Eguchi