Fujitsu Corporation

Shinji Fujimoto

Mitsuhiro Izumi

Hisashi Kaneko

Yukihiro Komura

Tsuneyori Ino

Kei Funabashi

Masato Shibuya

Mitsuaki Yoshida

Hiroyuki Iwahara

Keiji Aruga

Yoshiharu Matsuda

Keiichi Miyajima

Hiroshi Ishiyama

A rotary type actuator comprises an actuator assembly rotatably attached to a base and supporting a head at an end thereof via an arm and supporting a coil at the other end thereof, and a magnetic circuit unit having a yoke and a magnet secured to the base. The latch mechanism has a projection arranged from the inner periphery of the magnet provided in the magnetic circuit toward the rotational center and a latching magnet which produces an attraction force directed toward the latch position caused by leaking magnetic flux between itself and the projection near the latch position where the actuator assembly is in contact with the stopper and holds it at the latch position.

Disk apparatus and magnet for magnetic circuit

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 hard disk drive includes a base having a bottom plate. A magnetic body is embedded in the bottom plate. The magnetic body is allowed to serve as a magnetic shield in the hard disk drive. The magnetic body is allowed to have a sufficient thickness without requiring an additional space outside the base, since the magnetic body is embedded in the base. The magnetic field directed outside the base can reliably be absorbed at the magnetic body. The magnetic body may be received in a depression defined in the bottom plate. The depression may be formed based on a reduction in the thickness of the bottom plate.

Recording medium drive with magnetic body embedded in housing base opposite voice coil motor to suppress leakage flux

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

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

A recording disk drive includes a shroud wall spaced from a peripheral end of the recording disk by a gap equal to or smaller than 0.5 mm. A rectification groove is formed in the shroud wall at a position adjacent an area opposed to the peripheral end of the recording disk. Reduction in gap between the peripheral end of the recording disk and the shroud wall serves to reduce the amplitude of the flutter to be induced in the rotating recording disk. Moreover, as the gap gets smaller, the flutter reduces at a higher rate in response to increase of the depth of the rectification groove. Specifically, if the gap between the peripheral end of the recording disk and the shroud wall is set equal to or smaller than 0.5 mm, the groove can be made shallower so as to still efficiently suppress the flutter of the rotating recording disk.

Growing community of inventors

Kawasaki, Japan

Shinji Fujimoto