Hitachi, Ltd.

Hitachi Global Storage Technologies Netherlands B.v.

Japan Servo Co.,ltd.

Kenji Tomida

Hiroshi Nishida

Masaru Muranishi

Katsutoshi Nii

Shozo Saegusa

Yuuichi Yanagase

Kazuhiko Kawakami

Kouki Uefune

Hisanobu Kanamaru

Noriyuki Kumasaka

Takashi Kouno

Tsuyoshi Takahashi

Shinobu Yoshida

Tomoaki Inoue

Takeshi Yoshida

Masaaki Nakano

Takashi Matsuki

Takashi Kono

Mitsuyuki Tsuyuki

Kenji Mori

Takashi Yoshida

Hideaki Amano

Takashi Kohno

Hiroshi Uchida

Toshihiko Shimizu

Takao Suzuki

Isao Yoneda

Keiko Watanabe

Hiroki Kitahori

Takeshi Saito

Takenori Atsumi

Takeji Sumiya

Yuji Nishimura

Kazuhisa Shishida

Sachio Hatori

Kazuyoshi Hanada

Kazuaki Usui

Chikako Sakagami

Noritaka Otake

Yuji Ishima

Takeru Sato

Embodiments of the present invention securely latch an actuator rotated by an external impact. In an embodiment of the present invention, a latch and an actuator have a structure in which the latch can latch the actuator at two different swing angles. The swing angle of the latch is an angle in rotation centered on a rotational shaft (rotation angle). The latch may be engaged with the actuator at a shallow angle, or the latch may be engaged with the actuator at a deeper angle. Since the latch is able to latch the actuator at different swing angles, the actuator can be securely latched.

Disk drive device and magnetic disk drive

Embodiments of the present invention relate disk drives, and in particular to realizing a positioning accuracy equal to that of an actuator having the mountable maximum number of suspensions, in an actuator having the smaller number of suspensions than the mountable maximum number. An embodiment of a magnetic disk device includes an actuator having an arm to which a suspension for applying a predetermined load onto a slider with a magnetic head is attached, and an arm to which a plate is attached instead of having the suspension. The plate attached to the arm in place of the suspension has a partially small section with respect to a section perpendicular to an arm longitudinal direction (constricted part), and the constricted part is located between a plate leading end and an arm attachment part.

Magnetic disk device and head stack assembly

A disk drive. The disk drive includes a head, a moving mechanism, a first peak filter, an adaptive peak filter, and a filter controller. The head is configured to read servo data on a disk at sampling frequency. The moving mechanism is configured to move the head in proximity with a recording surface of the disk. The first peak filter has a fixed peak frequency and a variable gain, and is configured to be inserted into a servo loop. The servo loop is configured to position the head with position error signals between servo data read by the head and a target position. The adaptive peak filter has a variable peak frequency and a variable gain, and is configured to be inserted into the servo loop. The filter controller is configured to control the gain of the adaptive peak filter according to the gain of the first peak filter.

Disk drive and method for head servo control of the disk drive

Embodiments of the invention provide a magnetic disk drive promoting even higher densities, greater capacities, and further reduction in size, while relaxing component accuracy requirements. In one embodiment, the magnetic disk drive includes a magnetic disk receiving member and a magnetic disk holding member, a magnetic disk being rotatably held with the magnetic disk clamped therebetween. The receiving member makes a line contact with a surface of the magnetic disk on a circumference of a circle formed around a rotational axis of the magnetic disk.

Magnetic disk drive with line contact

A spindle motor for magnetic disc device includes a hub having an inside and an outer peripheral side on which a magnetic disc is mounted, a rotary shaft having an axial direction and coupled with the hub so as to be integrally rotated therewith, with the motor being arranged on the inside of the hub. The hub, the rotary shaft and a part of the motor constitute a rotary body. A radial bearing having a length in the axial direction of the rotary shaft, for supporting the rotary body in a direction crossing the rotary shaft, and a thrust bearing for supporting the rotary body in the axial direction of the rotary shaft are provided. The thrust bearing has an outer diameter greater than the length of the radial bearing, and is arranged at a position which is inside of the motor and diametrically inward of the hub.

Spindle motor and magnetic disc device using thereof having radial and thrust bearings

Shock-absorbing material made from a mixture of solid particles and viscous elastic material is arranged at the periphery of an information storage and retrieval device. When an external shock is applied to the device, the shock-absorbing material is greatly deformed and dissipates the shock energy by inner friction sufficiently to prevent damage to the inner mechanism of the device. The deformed shock-absorbing material can be restored to the original shape so that it is repeatedly usable. Furthermore, by comparing the deformed shape and the quick reference table provided with the device, the amount shock acceleration can be roughly determined. The device conforms to one of a series of dimensional standards for information storage and retrieval devices.

Information storage and retrieval device

A spindle motor used in a magnetic disc apparatus having a hub to which a magnetic disc is mounted and a rotary shaft to which the hub is fixed. The rotary shaft is located in a bearing casing having one end opened and the other end closed by a hydrodynamic pressure radial bearing, the rotary shaft being supported by a hydrodynamic pressure thrust bearing and the hydrodynamic pressure radial bearing. An inner diameter D and a width L of the hydrodynamic pressure radial bearing having a relationship of L/D<1.

Spindle motor and magnetic disc device with hydrodynamic bearings

Information storage and retrieval device provided with shock-absorbing mechanism

A rotary shaft is rotatably supported by a hydrodynamic fluid radial bearing and a hydrodynamic fluid thrust bearing which are excellent in shock resistance, an bearing arrangement in which vibration in a translation mode of the shaft, among vibration components caused by unbalance force exerted to the rotary shaft, is supported by the radial bearing, and vibration in conical mode is supported by the thrust bearing, magnetic fluid is used as lubrication oil, and a permanent magnet is located between the radial bearing and the thrust bearing so as to apply a magnetic attracting force between the rotary shaft and the thrust bearing so as to carry out axial positioning in order to use the magnetic disc device in an arbitrary attaching posture. With this arrangement, the magnetic disc device using such a bearing arrangement can enhance portability, thinning and antishock ability, and reduce noise and power consumption, thereby it is possible to provide a note-type personal computer with a high degree of reliability.

Spindle motor and magnetic disc device with hydrodynamic bearing

A disc device includes a housing, a fixed shaft at least partially disposed in the housing, wherein the fixed shaft is divided into two parts which are joined together. The disc device also includes one or more discs, a hub for loading the discs, at least a head for reproducing information recorded on each of the discs, and a drive system for moving the head to any position on each of the discs. A motor for driving the hub to rotate is provided outside the housing, and at least two fluid film bearings are provided so that the hub is supported by the fixed shaft so as to be rotatable.

Disc device

A disk drive unit includes a rotary member, which has a spindle, and has an information-recording disk fixedly mounted thereon, and a bearing unit rotatably supporting the spindle. The bearing unit includes a radial bearing device, provided in opposed relation to an outer peripheral surface of the spindle, and a thrust bearing device provided in opposed relation to a distal end surface of the spindle. The radial bearing device has a concentric arc-shaped bearing surface, which is concentric with the circular outer periphery of the spindle, and a non-concentric arc-shaped bearing surface which is non-concentric with the circular outer periphery of the spindle. The disk drive unit further includes a motor for imparting a rotational force to the spindle, and a lubricating fluid filled in the bearing unit.

Disk drive unit with hydrodynamic fluid bearing unit and disk device with said drive unit

In a magnetic disk apparatus, the spindle motor is provided with a hole that penetrates the hub in the axial direction thereof. The hole permits fluid pressure on the outside and inside of the hub to become balanced, reducing the axial fluid force caused by the rotation of the spindle motor. The apparatus further includes a bearing provided with a groove for dynamic pressure generation and a magnetic lubrication fluid which, in combination with a permanent magnet, prevents oil leakage and scattering.

Magnetic disk apparatus, including spindle motor having air flow passage in hub for pressure balance

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Odawara, Japan

Kenji Tomida