Fujitsu Corporation

Akihide Jinzenji

Tatsuro Sasamoto

Koichi Aikawa

Susumu Yoshida

Keiji Aruga

Tomoo Sukagawa

Yoshiaki Koizumi

Yasuyoshi Asao

A disk device comprises a disk having predetermined information sectors recorded at a constant interval; a head scanning the disk; and a disturbance-compensation unit obtaining an amount of a disturbance based on a time-interval measurement in reading the predetermined information sectors so as to compensate a position of the head according to the amount of the disturbance.

Disk device conducting a disturbance compensation based on a time-interval measurement in reading servo sectors recorded on a disk

A disk drive unit includes acceleration sensors mounted thereon. A sequence for calculating an amount by which a head actuator is adjusted during recording and readout operations is changed based on an output from the acceleration sensors.

Disk drive unit and control method for same

A magnetic disk unit has two actuators each rotating on a common rotary shaft. The two actuators are driven by a voice coil motor. The voice coil motor comprises: a magnetic circuit comprising a magnet provided for the two actuators on a common basis and two yokes, which are associated with the two actuators, respectively, said two yokes being disposed at both sides between which the magnet intervenes; and two coils provided for the two actuators, respectively.

Storage device

A small-sized rotational vibration testing apparatus having a wide band of measuring frequencies and capable of directly driving a rotary table ( ) to oscillate or vibrate in a rotational direction under the action of torque generated by a vibration applying mechanism. The rotary table ( ) is rotatably mounted on a base ( ), and a plurality of coil frames ( ) each having a coil ( ) attached thereto are mounted on a flange ( ) of the rotary table ( ) at an equal circumferential pitch or interval about its axis of rotation. A plurality of magnetic circuits ( ) are fixedly secured to the base ( ) in such a manner that the center of each coil ( ) is positioned at the center of an associated magnetic circuit ( ).

Rotational vibration testing apparatus

Disclosed is a calibration method for an acceleration sensor in a storage device for calibrating and a storage device, an enclosure for calibrating the acceleration sensor for compensating a vibration of an enclosure in a state of its being mounted in a storage drive. The calibration method and mode comprises a step of exciting a actuator of the drive by flowing a drive current having a predetermined current value, a step of calculating the acceleration of the enclosure of the drive from the predetermined current value and a mechanical transfer function of the storage device, a step of detecting a measured value of the acceleration sensor, and a step of calculating a sensitivity of the acceleration sensor from the calculated acceleration and from the detected measured value. The acceleration sensor is calibrated in the state of its being mounted in the disk drive, and hence the sensitivity can be precisely calibrated.

Growing community of inventors

Kawasaki, Japan

Akihide Jinzenji