Fujitsu Corporation

Toshiba Storage Device Corporation

Yoshifumi Obara

Takeshi Hara

Shigenori Yanagi

Yukio Abe

Mitsuo Kamimura

Satoshi Yamashita

Takao Abe

Shunji Saitou

According to an aspect of an embodiment, an apparatus, includes: a medium having inner and outer edges and including first and second servo regions extending radially, and containing first and second servo information written thereon, respectively, the first servo region extending outwardly from the inner edge to cover tracks, the first and second servo region having positioned adjacently across a circular boundary; a head for reading out said first servo information and said second servo information; and a processor for executing a process comprising: reading out the first or second servo information; and when controlling the track position across the boundary, adjusting the relation of the first and second servo information across the boundary in control the track position.

Data storage device

A storage device receives and holds a storage medium that is subjected to first servo writing processing for writing servo information, a Gray code of which is offset, from an inner cylinder or an outer cylinder to a predetermined cylinder and, after the first servo writing processing, subjected to second servo writing processing for writing servo information from an opposite direction to the predetermined cylinder and in which Gray codes are written to be offset not to overlap in the first or second servo writing processing and the pieces of servo information having different mark patterns are written in the first servo writing processing and the second servo writing processing. The storage device acquires cylinder information and mark patterns from the servo information written in the held storage medium and controls a position of a head based on the acquired cylinder information and mark patterns.

Storage device and servo information writing method

A storage medium (magnetic disk) in a storage device (magnetic disk device) includes a disk that stores therein data, a head that reads and writes data, a voice motor coil (VCM) that controls the head, and a ramp where the head is retracted. The storage device detects a current used for speed control during unloading of the head, and determines whether the current exceeds a predetermined value. The storage device detects a head position where the current exceeds a predetermined value as a ramp position, stores the ramp position, and unloads the head based on the ramp position.

Ramp-position detecting device, ramp-position detecting method, and storage device

A calculating unit calculates an interval time from a detection of a servo sync mark until a detection of an adjacent servo sync mark, for all servo sync marks on a track of a disk-shaped recording medium. A measuring unit measures, based on the calculated interval time, a deviation amount between a link interval time that represents the interval time between a servo sync mark recorded first and a servo sync mark recorded last and an ideal interval time that represents the link interval time when it is assumed that all the servo sync marks on the track are written at equal intervals.

Storage apparatus, storage apparatus control method, and computer product

A storage device configured to load and unload a head against a storage medium, includes a latch mechanism configured to latch the unloaded head, a head moving mechanism configured to move the head, a measuring part configured to measure an unlatch force necessary for unlatching the head latched by the latch mechanism, by applying a constant electrical current to the head mechanism so that the head is moved in a load direction, by measuring a back electromotive voltage, and calculating a moving speed and acceleration of the head, a storing part configured to store information indicating the measured unlatch force in the storage device, and a control part configured to apply a driving electrical current corresponding to the stored information to the head moving mechanism where the head is latched by the latch mechanism at the time of loading.

Storage device

A storage device, which comprises a storage media, a spindle motor which spins the storage media, a head unit which records and reads the data to the storage media, an actuator which carries out the positioning operation to the head unit on the storage media, a loading and unloading system which controls the actuator and carries out the unload operation that withdraws the head unit from the storage media and the loading operation that shifts the head unit onto the storage media, and a measurement means which measures the unloading energy required for the unload operation.

Growing community of inventors

Higashine, Japan

Yoshifumi Obara