Abstract: A head actuator assembly includes a carriage assembly including a bearing portion, first and second suspension assemblies extending from the bearing portion and each configured to support a head, and wire traces provided on each of the first and second the suspension assemblies and each including one end connected to a respective head and a connection end portion having connection terminals, and a flexible printed circuit board unit electrically connected to the wire traces through the connection terminals on both of opposing sides of the carriage assembly.

Abstract: In a magnetic disk device, a magnetic circuit drives an actuator carrying a magnetic head, so that the magnetic head is moved to a target track on a surface of a magnetic disk. A base has a threaded-hole part to which the magnetic circuit is fastened with a screw. A blocking member is provided to enclose a gap which is formed between the magnetic circuit and the threaded-hole part when the magnetic circuit is fastened to the threaded-hole part.

Abstract: In a magnetic disk drive having a magnetic circuit for moving a magnetic head by driving an actuator having the magnetic head mounted thereon, to a target track, and a base having a height criterion member for carrying out positioning in a height direction of the magnetic circuit as a result of the magnetic circuit being fixed thereto, wherein in a condition in which the magnetic circuit is fixed to the height criterion member, a space is provided between the base and a bottom surface, a spring member is provided for applying force to the magnetic circuit in such a direction that the magnetic circuit is apart from the bottom surface.

Abstract: In a magnetic disk device, a magnetic circuit drives an actuator carrying a magnetic head, so that the magnetic head is moved to a target track on a surface of a magnetic disk. A base has a threaded-hole part to which the magnetic circuit is fastened with a screw. A blocking member is provided to enclose a gap which is formed between the magnetic circuit and the threaded-hole part when the magnetic circuit is fastened to the threaded-hole part.

Abstract: A magnetic disk apparatus for reading and writing information to a magnetic disk including a motor for rotating the magnetic disk mounted thereon; a disk-shaped clamp for mounting the magnetic disk on the motor by screw fastening; and a C-shaped balancer for adjusting the rotary balance of the magnetic disk and mounted on the outer surrounding portion of the clamp, wherein the C-shaped balancer has a generally rectangular cross-section.

Abstract: A disc unit includes a head that records information onto and/or reproduces information from a disc, a suspension that includes a top surface and a side surface, and supports the head on the top surface, a flexible printed circuit board attached to the side surface of the suspension through an air gap, the flexible printed circuit board transmitting a signal indicative of the information to and from the head, and a damper that damps oscillation of the flexible printed circuit board.

Abstract: 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.

Abstract: For a magnetic disk apparatus for reading and writing information to a magnetic disk in the present invention, the recessed portion of the cover of the magnetic disk apparatus has a two-level structure; the space between the inner surface of the recessed portion, corresponding to the region of the magnetic disk surface which the actuator arm does not traverse, and the surface of the magnetic disk is made as narrow as possible. The air flow generated in that space by the rotation of the magnetic disk is thereby suppressed and as a result, magnetic disk resonance is suppressed. Also, the noise level is further suppressed by having two layers of damping plates attached to the outer surface of the cover.

Abstract: A disc unit includes a head that records information from and/or reproduces information onto a disc, a suspension that includes a top surface and a side surface, and supports the head on the top surface, a flexible printed circuit board attached to the side surface of the suspension through an air gap, the flexible printed circuit board transmitting a signal indicative of the information to and from the head, and a damper that damps oscillation of the flexible printed circuit board.

Abstract: 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.

Abstract: For a magnetic disk apparatus for reading and writing information to a magnetic disk in the present invention, the recessed portion of the cover of the magnetic disk apparatus has a two-level structure; the space between the inner surface of the recessed portion, corresponding to the region of the magnetic disk surface which the actuator arm does not traverse, and the surface of the magnetic disk is made as narrow as possible. The air flow generated in that space by the rotation of the magnetic disk is thereby suppressed and as a result, magnetic disk resonance is suppressed. Also, the noise level is further suppressed by having two layers of damping plates attached to the outer surface of the cover.

Abstract: A cover seal seals an opening of a housing body and encloses a cover for the opening in cooperation with the housing body. The rigidity of the cover seal is reinforced by a metallic sheet or a multiplayer synthetic resin sheet, so that vibration of the cover seal is prevented even if an air stream is a seam between the housing body cover acts on the cover seal from behind.

Abstract: 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.

Abstract: A recording disk drive comprises a shroud wall spaced from an 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.

Abstract: Disclosed herein is a magnetic disk drive including a spindle shaft fixed to a base, a coil mounted on the spindle shaft, a spindle hub rotatably mounted on the spindle shaft, a magnetic disk fixed to the spindle hub and having a plurality of tracks, a permanent magnet fixed to the spindle hub, a magnetic head for reading/writing information from/to the magnetic disk, and an actuator for moving the magnetic head across the tracks of the magnetic disk. The magnetic disk drive further includes a cover fixed to the base and having a hole at a position corresponding to the spindle shaft, a first metal washer placed on the cover at a portion around the hole, a second metal washer for sandwiching the cover at the portion around the hole in cooperation with the first metal washer, and a screw for securing the first and second metal washers to the spindle shaft.

Abstract: A disk device has a housing structure capable of reducing unnecessary vibrations of the base of the disk device by improving the rigidity thereof. A bath-tub type base of the disk device includes a damping structure on the bottom or on the sides adjacent to the bottom for attenuating the vibrations of the base. Apparatus for writing a reference signal into the disk of the device using a reference head with a head insertion hole formed in the base is also provided.

Abstract: A cover seal closes an opening of a housing body and enclose a cover for the opening in cooperation with the housing body. The rigidity of the cover seal is reinforced by a metallic sheet or a multilayer synthetic resin sheet, so that vibration of the cover seal is prevented even if air stream in a seam between the housing body and cover acts on the cover seal from the behind. Noise can be suppressed.

Abstract: A cover seal seals an opening of a housing body and encloses a cover for the opening in cooperation with the housing body. The rigidity of the cover seal is reinforced by a metallic sheet or a multiplayer synthetic resin sheet, so that vibration of the cover seal is prevented even if air stream in a seam between the housing body and cover acts on the cover seal from the behind.

Abstract: A method for incorporating a disk medium into a magnetic disk drive, in which the rotation center of the disk medium when a servo track information is written onto the disk medium (STW) coincides with the rotation center thereof when the disk medium is incorporated into the disk apparatus. A reference marker is provided as a positioning reference on a part of the disk medium. The disk medium is incorporated into a STW apparatus so that STW is performed on the disk medium. The disk medium is also incorporated into the magnetic disk drive in such a manner that a distance from an axis of rotation center of the disk medium to the reference marker is the same as when the STW was performed onto the disk medium.