Hitachi, Ltd.

Hitachi Global Storage Technologies Netherlands B.v.

Hitachi Global Storage Technologies Japan, Ltd.

Marutomo Goto

Takashi Kouno

Shigeo Nakamura

Takashi Yamaguchi

Masahiko Sega

Satomitsu Imai

Hitoshi Shindo

Kei Yasuna

Toshio Matsushita

Yasuhiro Yoshimura

Yoshinori Takeuchi

Takako Hayakawa

Toshihiro Yamada

Shozo Saegusa

Takashi Yoshida

Yuzo Yamaguchi

Hideaki Amano

Shinobu Yoshida

Hiromu Hirai

Ryoji Okada

Hidehiko Numasato

Toshiaki Makino

Satoru Yamaura

Kazuhide Ichikawa

Hiroshi Daito

Yasuhiro Matsuda

Yuichi Koizumi

Hideyuki Kimura

Taichi Sato

Takashi Kono

Akio Takatsuka

Kenichiro Sugiyama

Embodiments of the invention provide a magnetic disk drive having improved vibration characteristics and a reduced size. In one embodiment, a magnetic disk drive comprises: a motor shaft for rotating a magnetic disk; a sleeve for rotatably supporting the motor shaft; and a motor hub into which the motor shaft is press fit. The motor hub supports the magnetic disk and includes a projection portion having an inner surface and an outer surface. The inner surface is in contact with the press-fit motor shaft in directions perpendicular to the rotational axis of the motor shaft. The outer surface faces the sleeve.

Magnetic disk drive with improved vibration characteristics

Embodiments of the invention provide a magnetic disk drive that allows members to be mounted onto a base simply and accurately. In one embodiment, a magnetic disk drive comprises: a base; a disk assembly including at least one magnetic disk and mounted rotatably on the base; and an actuator assembly including at least one actuator having a magnetic head and mounted swingably on the base. The base is formed with a guide. The guide functions to guide, when a member to be disposed on the base is to be mounted, the member from a corresponding initial placement position of the member on the base to a target position, at which the member is to be disposed. Further, the guide includes a positioning portion, against which the member abuts at the corresponding target position.

Magnetic disk drive and base with guide

A rotational member and a stationary member included in a spindle motor provided with air bearings are electrically connected while the bearing is rotating, and abrasion of the rotational member and the stationary member at stages of starting and stopping and damaging the rotational member and the stationary member by external shocks that may be exerted thereon during transportation and handling are avoided. In one embodiment, a sleeve is formed integrally with a motor base. The sleeve has an inside surface serving as a radial-bearing surface that forms a radial bearing together with the outside surface of a rotational shaft, and a thrust-bearing surface that forms thrust bearing together with a thrust plate attached to the rotational shaft. The radial-bearing surface of the sleeve is provided with a recess (groove) for holding lubricating oil while the rotational shaft is rotating. A gap not forming a bearing is formed between the circumference of the thrust plate and the inside surface of the sleeve to hold the lubricating oil while the rotational shaft is rotating.

Spindle motor and magnetic disk drive

Servo-write arrangements to self-record servo signals onto magnetic disk arrangements.

Magnetic disk device and servo write method

A magnetic disk device having a magnetic disk for recording information, a spindle motor for driving the magnetic disk for rotation, a magnetic head for reading information from the magnetic disk, a carriage arm for supporting the magnetic disk, a voice coil motor for moving the carriage arm, a loading/unloading mechanism for retracting the carriage arm from a position on the magnetic disk, and a shroud for forming a peripheral wall. The magnetic device includes an air passage positioned between the loading/unloading mechanism and the shroud.

Magnetic disk device

The magnetic disk apparatus includes a magnetic disk for storing thereinto information; a head equipped with a recording conversion element for writing information into the magnetic disk and a reproducing conversion element for reading information from the magnetic disk; an actuator arranged by a suspension for supporting the head so as to move the head on the magnetic disk, and also a drive apparatus for driving the suspension; and a stopper for limiting a movable range of the actuator, whereby a distance between a reproduction element and a recording element is measured and also a track width of the magnetic disk is measured in order to execute a self-servo write operation.

Magnetic disk apparatus and servo signal recording method

Return channels , and are formed to guide air flowing through a clearance between a magnetic disk ( ) and a shroud ( ) so that the air flows behind a voice coil motor, bypasses a loading/unloading mechanism ( ) and flows toward a region on the lower side of the loading/unloading mechanism with respect to the rotating direction of the magnetic disk ( ). Thus, production of turbulent flow in the vicinity of the loading/unloading mechanism is controlled. Fluttering of the magnetic disk ( ) can be controlled by placing a filter in one of the return channels.

A disk locating actuator of a disk apparatus has a carrier member carrying a head and a curved flexible printed circuit fixed at its one end to the carrier member and at its other end to a base. Angles at which the flexible printed circuit is fixed are suitably determined so as to diminish any dynamic reacting force produced by vibration of the flexible printed circuit, thus ensuring high degree of head locating precision.

Head locating actuator having reduced susceptibility to dynamic reaction

A magnetic disk unit comprising a one-piece carriage structure having a small thermal off-tracking amount, with the carriage structure including a rotary shaft; guide arms integrally supported on a guide-arm retainer at their proximal ends and extending independently and parallely; bearing retainers formed on both ends of the guide-arm retainer; and bearings fixed on the bearing retainers rotatably connecting the guide-arm retainer to the rotary shaft. A center line in a direction of thickness of the outermost guide arm is located outside of that of the bearing in a direction of height thereof, and a concave portion is continuously formed on the bearing retainer. Thermal coefficients of expansion of the guide arms and the guide-arm retainer are substantially equal, with the carriage structure being fashioned of an alloy mainly containing Al and Si, eutectic crystal Si particles in the guide arm and/or the guide-arm retainer. The average value of the longest eutectic crystal Si particles therein is 1.6 .mu.m or less or the number of the eutectic crystal Si particles if 5.0 or more per 100 .mu.m.sup.2. In the carriage of manufacturing the carriage of the carriage structure is heated for five to fifteen hours at a temperature of 300.degree. to 500.degree. C. after die casting.

Magnetic disk unit and manufacturing method of carriage structure thereof

A transducer supporting device having a rigid-structure support member connected to a guide arm, and a flexible-structure support member attached to the rigid-structure support member on the side of a free end of the same. Portions of the rigid-structure and flexible-structure support members connected to each other are constructed so that the shear center of these portions is brought closer to the connection surface.

Transducer supporting device for supporting a transducer in a rotary

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Odawara, Japan

Marutomo Goto