Patents by Inventor Masahiko Sega

Masahiko Sega has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20030189785
    Abstract: A magnetic disk apparatus includes magnetic disks stacked on a rotating shaft, arms supporting magnetic heads, a rotary actuator for moving the arms, and a housing forming at least a part of an arcuate-shaped shroud which substantially surrounds a portion of side surfaces of the magnetic disks so as to define a gap between the shroud and the portion of the side surfaces of the magnetic disks. The arcuate-shaped shroud has portions delimiting an open space adjacent to another portion of the side surfaces of the magnetic disks which is located on a downstream side of the arms relative to an air flow which moves on surfaces of the magnetic disks. A bypass channel provides air flow to the disks in a region of the open space at a reduced pressure on the downstream side of the arms with respect to pressure at an upstream side of the arms.
    Type: Application
    Filed: April 9, 2003
    Publication date: October 9, 2003
    Inventors: Hayato Shimizu, Masao Iwakura, Shigeo Nakamura, Kazuo Sakai, Shigenori Togashi, Masayuki Kaiho, Toshiaki Kobari, Mikio Tokuyama, Satomitsu Imai, Shozo Saegusa, Masahiko Sega, Toshihisa Okazaki, Yuzo Yamaguchi
  • Patent number: 6600626
    Abstract: A magnetic disk apparatus arranged in a housing having a plurality of magnetic disks stacked on a rotating shaft, arms supporting thereon magnetic heads and adapted to be inserted between said magnetic disks, a rotary actuator for moving the arms, a housing forming at least a part of an arcuate-shaped shroud which substantially surrounds a portion of side surfaces of the magnetic disks so as to permit movement of the arms and which is concentric with the magnetic disks so as to define a gap between the shroud and the portion of the side surfaces of said magnetic disks. The gap defined between the outer peripheral end surfaces of the magnetic disks and the shroud is in a range of 0.1 mm to 0.6 mm.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: July 29, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Hayato Shimizu, Masao Iwakura, Shigeo Nakamura, Kazuo Sakai, Shigenori Togashi, Masayuki Kaiho, Toshiaki Kobari, Mikio Tokuyama, Satomitsu Imai, Shozo Saegusa, Masahiko Sega, Toshihisa Okazaki, Yuzo Yamaguchi
  • Patent number: 6560066
    Abstract: Return channels 45a, 45b, 45c, and 50 are formed to guide air flowing through a clearance between a magnetic disk (11) and a shroud (41) so that the air flows behind a voice coil motor, bypasses a loading/unloading mechanism (31) and flows toward a region on the lower side of the loading/unloading mechanism 31 with respect to the rotating direction of the magnetic disk (11). Thus, production of turbulent flow in the vicinity of the loading/unloading mechanism 31 is controlled. Fluttering of the magnetic disk (11) can be controlled by placing a filter 60 in one of the return channels.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: May 6, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Satomitsu Imai, Takashi Kouno, Marutomo Goto, Shigeo Nakamura, Masahiko Sega
  • Publication number: 20030058575
    Abstract: A magnetic disk device includes a magnetic disk for recording information, a spindle motor for driving the magnetic disk for rotation, a magnetic head for writing information to and reading information from the magnetic disk, a carriage arm supporting the magnetic head, a voice coil motor for moving the carriage arm, a shroud forming a peripheral wall, an air passage passing between the voice coil motor and the shroud and connecting an upper side of the carriage arm with respect to the direction of rotation of the magnetic disk to a lower side of the carriage arm, and a filter. The filter is placed away from an outer edge of the magnetic disk and wholly within the air passage to clean air inside the disk drive.
    Type: Application
    Filed: November 5, 2002
    Publication date: March 27, 2003
    Inventors: Satomitsu Imai, Takashi Kouno, Marutomo Goto, Shigeo Nakamura, Masahiko Sega
  • Patent number: 6501645
    Abstract: When supporting an HDA including an H/DA and an electronic control circuit board for controlling the same in a fixed frame (drive bay) of upper level apparatus by means of elastic or “soft” fixation, counterforce of an FPC cable gives it bad influence. When rigidly securing the HDA in a translational motion direction while attaining soft fixation in a direction of rotation, the HDA is rotatably supported with its center of gravity being as the center of rotation in a soft secure/support mechanism as taught from Published Japanese Patent Application No. 8-161880 (JP-A-8161880) for example; however, in the case of employing one of commercially available general purpose HDAs, this is disposed so that a bent or curved portion of its cable is identical in position to the rotation center or placed at a nearby location of the gravity center to thereby preclude the stiffness of an FPC cable hardly affects such rotatable support mechanism.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: December 31, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Shigeyuki Hanazawa, Masahiko Sega, Toshiaki Kojima, Yasuhiro Matsuda
  • Publication number: 20020181149
    Abstract: A magnetic disk apparatus arranged in a housing having a plurality of magnetic disks stacked on a rotating shaft, arms supporting thereon magnetic heads and adapted to be inserted between said magnetic disks, a rotary actuator for moving the arms, a housing forming at least a part of an arcuate-shaped shroud which substantially surrounds a portion of side surfaces of the magnetic disks so as to permit movement of the arms and which is concentric with the magnetic disks so as to define a gap between the shroud and the portion of the side surfaces of said magnetic disks. The gap defined between the outer peripheral end surfaces of the magnetic disks and the shroud is in a range of 0.1 mm to 0.6 mm.
    Type: Application
    Filed: March 22, 2002
    Publication date: December 5, 2002
    Inventors: Hayato Shimizu, Masao Iwakura, Shigeo Nakamura, Kazuo Sakai, Shigenori Togashi, Masayuki Kaiho, Toshiaki Kobari, Mikio Tokuyama, Satomitsu Imai, Shozo Saegusa, Masahiko Sega, Toshihisa Okazaki, Yuzo Yamaguchi
  • Publication number: 20020075592
    Abstract: In a magnetic disk apparatus including a plurality of magnetic disks mounted on a spindle, arms supporting magnetic heads, a rotary actuator for the arms, and a housing having an arcuate-shaped shroud, the improvement wherein gaps between the shroud and the sides of outer peripheries of the magnetic disks are larger than 0.1 mm and less than 0.6 mm. An open space is located, downstream of the arms, with respect to an air flow on surfaces of the magnetic disks, the open space being devoid of the shroud. An opening is provided in the shroud, upstream of the arms with respect to the air flow and having a greater width than a width of the gaps defined between the magnetic disks and the shroud, and a bypass channel is provided which communicates between the opening and the open space.
    Type: Application
    Filed: December 20, 2001
    Publication date: June 20, 2002
    Inventors: Mikio Tokuyama, Hayato Shimizu, Satomitsu Imai, Shozo Saegusa, Masahiko Sega, Toshihisa Okazaki, Yuzo Yamaguchi, Masao Iwakura, Shigeo Nakamura, Kazuo Sakai, Shigenori Togashi, Masayuki Kaiho, Toshiaki Kobari
  • Patent number: 6369977
    Abstract: Return channels 45a, 45b, 45c, and 50 are formed to guide air flowing through a clearance between a magnetic disk (11) and a shroud (41) so that the air flows behind a voice coil motor, bypasses a loading/unloading mechanism (31) and flows toward a region on the lower side of the loading/unloading mechanism 31 with respect to the rotating direction of the magnetic disk (11). Thus, production of turbulent flow in the vicinity of the loading/unloading mechanism 31 is controlled. Fluttering of the magnetic disk (11) can be controlled by placing a filter 60 in one of the return channels.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: April 9, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Satomitsu Imai, Takashi Kouno, Marutomo Goto, Shigeo Nakamura, Masahiko Sega
  • Publication number: 20020039253
    Abstract: Return channels 45a, 45b, 45c, and 50 are formed to guide air flowing through a clearance between a magnetic disk (11) and a shroud (41) so that the air flows behind a voice coil motor, bypasses a loading/unloading mechanism (31) and flows toward a region on the lower side of the loading/unloading mechanism 31 with respect to the rotating direction of the magnetic disk (11). Thus, production of turbulent flow in the vicinity of the loading/unloading mechanism 31 is controlled. Fluttering of the magnetic disk (11) can be controlled by placing a filter 60 in one of the return channels.
    Type: Application
    Filed: November 9, 2001
    Publication date: April 4, 2002
    Inventors: Satomitsu Imai, Takashi Kouno, Marutomo Goto, Shigeo Nakamura, Masahiko Sega
  • Publication number: 20020039251
    Abstract: Return channels 45a, 45b, 45c, and 50 are formed to guide air flowing through a clearance between a magnetic disk (11) and a shroud (41) so that the air flows behind a voice coil motor, bypasses a loading/unloading mechanism (31) and flows toward a region on the lower side of the loading/unloading mechanism 31 with respect to the rotating direction of the magnetic disk (11). Thus, production of turbulent flow in the vicinity of the loading/unloading mechanism 31 is controlled. Fluttering of the magnetic disk (11) can be controlled by placing a filter 60 in one of the return channels.
    Type: Application
    Filed: January 26, 2001
    Publication date: April 4, 2002
    Inventors: Satomitsu Imai, Takashi Kouno, Marutomo Goto, Shigeo Nakamura, Masahiko Sega
  • Patent number: 6115213
    Abstract: A magnetic disk drive which is to be used for recording and/or reproducing information, and a bearing assembly for use in the same magnetic disk drive. The bearing assembly includes two bearings of different diameters, of which a small-diameter bearing is arranged within an inner periphery of a large-diameter bearing. The two bearings are joined by means of bearing coupling members for connecting respectively inner rings and outer rings of the bearings. The small-diameter bearing is arranged within the inner periphery of the large-diameter bearing, and therefore a height of the bearing assembly can be made thinner to about one and a half times a height of a single bearing. It is therefore possible to make the magnetic disk drive smaller and thinner by employing this bearing assembly.
    Type: Grant
    Filed: September 11, 1997
    Date of Patent: September 5, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Ikeda, Shinobu Yoshida, Masahiko Sega
  • Patent number: 5862011
    Abstract: A magnetic disk device has a large capacity with a small and thin structure and includes a spindle system, an actuator system, a control package for controlling the systems, and a PCMCIA connector. The spindle system is of an in-hub structure wherein two magnetic disks are rotated in inside diameter portions of the magnetic disks. The actuator system has sliders mounting magnetic heads for writing and reading magnetic information to and from the magnetic disks, guide arms and suspension structures. The suspension structures also include a coil, a magnetic circuit for imparting a drive force in cooperation with the coil, a coil holder for supporting the coil, a pivot sleeve for rocking the guide arms, the coil holder and spacers which are integrally laminated to each other, bearings and a pivot shaft. The PCMCIA connector connects to the control package and is fixed by the housing and a package cover.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: January 19, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Masahiko Sega, Tomio Suzuki, Tsuyoshi Takahashi, Hiroyuki Mitsuhashi, Tetsuo Yuki, Takashi Matsuki
  • Patent number: 5416658
    Abstract: Degradation of a detector-head positioning in an information storage device using a rotary recording medium may be prevented. A reaction force which gives a vibration to a positioning mechanism in a magnetic disk drive generally occurs when the detector heads seek a destination track on a rotary recording medium. This vibration or impact may be decreased or eliminated if an actuator magnet is supported on a linear-slider member or a rotary-slider member. Sliding motion is received with a pneumatic spring to softly result in no vibration being transmitted to the spindle or other positioning mechanism. The pneumatic spring can drastically reduce a proper vibration frequency of the positioning mechanism (magnetic-circuit support) to such an extent that an electrical servo system can catch the vibration frequency and can hold down a location error. Even if a reaction force is too big to prevent resonance from being caused, the pneumatic spring can quickly attenuate the reaction force using its own throttle hole.
    Type: Grant
    Filed: May 26, 1993
    Date of Patent: May 16, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Masahiko Sega, Jiro Kaneko, Tsuyoshi Takahashi
  • Patent number: 5267111
    Abstract: In a voice coil motor having a voice coil, and a magnetic circuit which generates a magnetic flux traversing the voice coil; the magnetic circuit includes a yoke which is divided so as to form a plurality of magnetic paths traversing the voice coil and which is provided with hollows, and adjustment members which are inserted into the hollows so as to adjust the magnetic fluxes of the magnetic paths independently of one another.
    Type: Grant
    Filed: November 8, 1991
    Date of Patent: November 30, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Yuji Nishimura, Tsuyoshi Takahashi, Masahiko Sega, Jyousei Shimizu, Tomio Suzuki
  • Patent number: 5241435
    Abstract: A method of recording a servo signal on each track of a magnetic disk includes a first signal for demagnetizing the magnetic disk and a second signal for forming the servo signal. The recording width (core width) of the magnetic head is made greater than the width of the track. Parts for recording signals and not recording signals are set in each track. The first and second signals are selected and recorded in the signal recording part, thereby to form the servo signal. Current to be conducted to the magnetic head is cut in the part for not recording signals, and the track is skipped to the next part for recording signals. When the recording of the track has ended, the magnetic head is moved to the next track, and the above steps are repeated.
    Type: Grant
    Filed: June 21, 1990
    Date of Patent: August 31, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Shigeyoshi Saito, Yuji Hata, Takuji Ogawa, Jyousei Shimizu, Tsuyoshi Takahashi, Masahiko Sega, Kazuo Ono