Fujitsu Corporation

Yukihiro Komura

Hisashi Kaneko

Mitsuhiro Izumi

Tsuneyori Ino

Shinji Fujimoto

Yoshiaki Nagasawa

Kei Funabashi

Tomoo Sukagawa

Katsuaki Ishida

Osamu Yamazaki

Masato Shibuya

Masaharu Sugimoto

Mitsuaki Yoshida

Masahide Kanegae

Tsuyoshi Furukawa

Hiroyuki Iwahara

Shinichi Fukuzawa

Masaki Jinbo

Hajime Miura

Hiroshi Ishiyama

A data placement program causes a computer to execute a process of data placement in a main memory and a cache. When performing an operation using a first data groups and second data groups to generate pieces of operation result data representing operation results of the operation, based on a size of one piece of the operation result data and a size of an operation result area storing some of the plurality of pieces of operation result data in the cache memory, determining a number of the first data groups and a number of the second data groups, both corresponding to the some pieces of operation result data, and placing the plurality of first data groups and the plurality of second data groups in the main memory based on the determined number of the first data groups and the determined number of the second data groups.

Computer-readable recording medium storing data placement program, processor, and data placement method

A fixing member is spaced from a head actuator by a predetermined distance. A flexible printed circuit board extends at least from the head actuator to the fixing member. The flexible printed circuit board is superposed on the surface of the fixing member. A viscoelastic layer and a protecting layer are overlaid on the surface of the flexible printed circuit board. A clip clips all the fixing member, the flexible printed circuit board, the viscoelastic layer and the protecting layer together. When a head slider is positioned, the head actuator changes its attitude relative to a recording disk. The inertial force based on the rotation causes the first flexible printed circuit board to vibrate when the actuator block stops rotating. The viscoelastic layer serves to absorb this residual vibration of the first flexible printed circuit board. Vibration of the flexible printed circuit board can be suppressed.

Recording disk drive capable of suppressing vibration of flexible printed circuit board

A magnetic disk device comprises a magnetic disk in which a data zone is formed. An actuator has a voice coil and a head slider carrying a magnetic head, the actuator being swung to move the magnetic head over the disk between an innermost position of the data zone and an outermost position of the data zone. A magnet has a magnetization center and is opposed to the voice coil so that a voice coil motor which swings the actuator is formed, the magnet having a north pole and a south pole confronting each other via the magnetization center. The magnetic disk device is provided so that a deviation of a center of the voice coil from the magnetization center when the magnetic head is in the innermost position of the data zone is substantially equal to a deviation of the center of the voice coil from the magnetization center when the magnetic head is in the outermost position of the data zone.

Magnetic head actuator with centered deviation

A guide pin is set in common in first and second voids defined in the peripheries of first and second flexible printed wiring boards. The second void has the shape identical to the shape of the first void. When the guide pin rotates around a rotation axis so as to bring the guide pin in contact with the peripheries of the first and second flexible printed wiring boards inside the first and second voids, the first and second flexible printed wiring boards can be arranged. This leads to arrangement of the first and second flexible printed wiring boards at a time in a facilitated manner.

Head suspension assembly having flexible printed wiring board with alignment void arrangement

Magnetic head actuator with equalized deviation

A thermal component is mounted on the front surface of an isolator sheet within a first specific area. A thermally-conductive material is located on the back surface of the isolator sheet on the back of the first specific area. An electrically-conductive material is located on the front surface of the isolator sheet within a second specific area. A thermally-insulating material is located on the back surface of the isolator sheet on the back of the second specific area. The flexible printed circuit board unit of this type allows heat of the thermal component to efficiently radiate from the thermally-conductive material. An increase in temperature can be suppressed in the thermal component. Heat can reliably stay in the electrically-conductive material when a solder material is applied to the surface of the electrically-conductive material. The solder material is allowed to reliably fuse.

Flexible printed circuit board unit contributing to reliable soldering and suppression of increased temperature

An actuator for moving heads in a disk unit having heads for reading or writing data from or on recording surfaces of disks driven to rotate, an actuator having arms for supporting the heads, a main FPC board having one end thereof supported by the actuator and the other end thereof supported by a body of the disk unit, and relay FPC boards placed along the arms of the actuator, which can realize a compact and thin size, resistive to noise, and permitting a reduction in manufacturing cost. A printed-circuit board is supported by an actuator, is electrically connected to a circuit unit in a body of a disk unit via a main FPC board, and is electrically connected to heads via relay FPC boards. Integrated circuits are mounted on the printed-circuit board.

Disk apparatus having an actuator for moving heads

A breather filter unit for a magnetic disk drive including a base and a cover fixed to the base, the cover having a vent. The breather filter unit includes a casing fixed to an inner surface of the cover, the casing having a vent inlet communicating with the vent of the cover and a vent outlet communicating with an inside of the magnetic disk drive, and a first filter contained in the casing at a position adjacent to the vent inlet, the first filter being formed from a plurality of fibers extending in a direction substantially parallel to that of an air flow from the vent inlet to the vent outlet. The breather filter unit further includes a second filter bonded to the casing so as to cover the vent outlet, and an activated carbon layer contained in the casing at a position between the first filter and the second filter.

Breather filter unit for magnetic disk drive

A head actuator for a magnetic disk drive unit which eliminates the possibility of track slip due to a mechanical external force and allows high-speed access. The head actuator includes a carriage having a body provided rotatably to a shaft fixed to a housing and an arm fixed to the body so as to extend substantially perpendicularly to the shaft, a supporting member mounted on the body on its side opposite to the arm with respect to the shaft, and a coil fixed to the supporting member and receiving a driving force from a static magnetic field. The supporting member is formed of a material having a specific gravity larger than that of a material forming the body of the carriage.

Growing community of inventors

Kawasaki, Japan

Yukihiro Komura