Hitachi, Ltd.

Hitachi Global Storage Technologies Japan, Ltd.

Kazuaki Usui

Keiko Watanabe

Hitoshi Ogawa

Tetsuya Hamaguchi

Kei Yasuna

Tsuyoshi Arai

Atsushi Okuyama

Seiichi Domyo

An information recording/reproducing system in which a host system making access to a magnetic disk apparatus can be limited to a specific one. A magnetic disk apparatus includes an authentication key generating block for generating an authentication key on the basis of physical characteristic(s) of the magnetic disk apparatus itself. The magnetic disk apparatus and the host system have, respectively, authentication key recording block for recording the authentication key and authentication data generating block for generating authentication data on the basis of the authentication key. Access from the host system to information of the magnetic disk apparatus is controlled based on the authentication data of the host system and the authentication data of the magnetic disk apparatus.

System for controlling host access to a storage device based on physical characteristics of the storage device

An acceleration detecting apparatus for a magnetic disk apparatus capable of detecting with high reliability the disturbances such as rotational and translational shocks and vibrations applied externally to the magnetic disk apparatus to thereby prevent destruction or the like damages of data recorded on a disk of the magnetic disk apparatus upon occurrence of off-track event under the influence of the disturbance. The apparatus includes a pair of acceleration detectors for detecting acceleration in two directions extending discretely in parallel to each other. The acceleration detectors are disposed at positions closer to the magnetic disk relative to a pivot shaft for a head supporting arm as viewed in a longitudinal direction of an oblong box-like casing of the magnetic disk apparatus in a plane which forms an angle not greater than 10 degrees relative to the plane of the magnetic disk. By employing the angular acceleration detectors in combination with an angular velocity detector, the rotational disturbances due to rotational shock/vibration can be detected with much enhanced reliability, and destruction of the data recorded on the magnetic disk due to the off-track read/write operation can positively be prevented.

Information recording disk apparatus

Growing community of inventors

Chiyoda, Japan

Kazuaki Usui