Patents by Inventor Kohji Serizawa

Kohji Serizawa 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).

  • Patent number: 7573671
    Abstract: Embodiments of the invention provide a disk device capable of diminishing oscillation of a disk caused by an air flow which is created with rotation of the disk. In one embodiment, a magnetic disk device comprises a rotatable magnetic disk, a base and a top cover for housing the magnetic disk inside, a flow uniforming wall disposed along an outer periphery of the magnetic disk, and a circulation filter for collecting dust present within the device. The flow uniforming wall is positioned in opposition to the outer periphery of the magnetic disk and has a step height at a position other than the position opposed to the disk outer periphery, with an opening being formed by a gap between the step height and the top cover. This opening serves as an inlet port to admit an air flow created with rotation of the magnetic disk, and the circulation filter collects dust contained in the admitted air flow.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: August 11, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kohji Serizawa, Hitoshi Tsujino, Hirokazu Tanizawa, Motoji Takemoto
  • Patent number: 7545599
    Abstract: Embodiments of the invention provide a disk drive suppressing a surface deformation of a top cover. In one embodiment, the disk drive includes a base and a top cover. The base accommodates a head assembly, a circuit unit, and a recording medium. The top cover is supported by the base at a plurality of inner points of support and peripheral edge points of support on a peripheral edge portion near a portion accommodating the head assembly and the circuit unit. The top cover covers the accommodating portion of the base. A vibration suppression member for suppressing vibration of the top cover is disposed in a polygon. The polygon has, as vertices, a plurality of inner points of support and, among the peripheral edge points of support, the peripheral edge points of support near the portion accommodating the head assembly and the circuit unit. The vibration suppression member is disposed at a position in the polygonal portion corresponding to an area near a loop of vibration in a surface of the top cover.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: June 9, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kohji Serizawa, Hitoshi Tsujino, Hirokazu Tanizawa, Takeji Sumiya
  • Publication number: 20060164751
    Abstract: Embodiments of the invention provide a disk drive suppressing a surface deformation of a top cover. In one embodiment, the disk drive includes a base and a top cover. The base accommodates a head assembly, a circuit unit, and a recording medium. The top cover is supported by the base at a plurality of inner points of support and peripheral edge points of support on a peripheral edge portion near a portion accommodating the head assembly and the circuit unit. The top cover covers the accommodating portion of the base. A vibration suppression member for suppressing vibration of the top cover is disposed in a polygon. The polygon has, as vertices, a plurality of inner points of support and, among the peripheral edge points of support, the peripheral edge points of support near the portion accommodating the head assembly and the circuit unit. The vibration suppression member is disposed at a position in the polygonal portion corresponding to an area near a loop of vibration in a surface of the top cover.
    Type: Application
    Filed: December 22, 2005
    Publication date: July 27, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kohji Serizawa, Hitoshi Tsujino, Hirokazu Tanizawa, Takeji Sumiya
  • Publication number: 20060132966
    Abstract: Oscillation of a spindle motor caused by a shock is to be suppressed. In one embodiment, an HDD according to an embodiment of the present invention comprises a base, a spindle motor for rotating a magnetic disk, the spindle motor being fixed to an inner surface of a base bottom, and a circuit board disposed on an outer surface of the base bottom. Plural outer screws fix the circuit board to the base bottom at outer end portions of the circuit board. Further, three or more inner screws fix the circuit board to the base bottom at inner positions of the circuit board with respect to the outer screws. The center of gravity of the spindle motor is positioned within a polygon defined by the three or more inner screws.
    Type: Application
    Filed: December 5, 2005
    Publication date: June 22, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kohji Serizawa, Hitoshi Tsujino, Takashi Tomita
  • Publication number: 20060132967
    Abstract: Embodiments of the invention provide a disk device capable of diminishing oscillation of a disk caused by an air flow which is created with rotation of the disk. In one embodiment, a magnetic disk device comprises a rotatable magnetic disk, a base and a top cover for housing the magnetic disk inside, a flow uniforming wall disposed along an outer periphery of the magnetic disk, and a circulation filter for collecting dust present within the device. The flow uniforming wall is positioned in opposition to the outer periphery of the magnetic disk and has a step height at a position other than the position opposed to the disk outer periphery, with an opening being formed by a gap between the step height and the top cover. This opening serves as an inlet port to admit an air flow created with rotation of the magnetic disk, and the circulation filter collects dust contained in the admitted air flow.
    Type: Application
    Filed: December 15, 2005
    Publication date: June 22, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kohji Serizawa, Hitoshi Tsujino, Hirokazu Tanizawa, Motoji Takemoto
  • Patent number: 6690540
    Abstract: A disk drive damper avoids matching a frequency band of a sound frequency peak generated by the rotation of a spindle motor and a resonant frequency of the damper. The damper is attached to a disk drive apparatus and enabled to repress vibration. The damper includes a flat base portion and wall-thickness portions that are thicker than the flat base portion. The damper is varied in shape more freely than conventional flat dampers. Consequently, the resonant frequency of the damper can be adjusted more freely than ever.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: February 10, 2004
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Yoshihiro Hirasaka, Kohji Serizawa, Shinichi Matsuzaki, Kohji Takahashi
  • Patent number: 6657812
    Abstract: A hard disk drive contains a disk assembly and a cylindrical disk container. The drive also includes a base around which a peripheral wall extends, a catching chamber including a partition wall partitioning the base into the catching chamber and a disk container, and a top cover functioning as a lid of the base. In addition, the hard disk drive has a first gasket as a first gasket section existing between the top cover and a peripheral wall of the base, and a second gasket as a second gasket section existing between the top cover and the partition wall of the catching chamber.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: December 2, 2003
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Kohji Serizawa, Yoshihiro Hirasaka
  • Patent number: 6633452
    Abstract: A hard disk drive apparatus is capable of reducing a noise effectively during operation and capable of enhancing the reliability of the drive. The hard disk drive has first and second ribs that are formed near a pivot for an actuator so that a tilt of the pivot is prevented when the actuator is operated. Also, vibration absorbing members are interposed between the first and second ribs on the side of a base and a cover so that the vibration absorbing members are brought into contact with the cover. These vibration absorbing members are located in an intermediate portion between fixing places for fixing the cover to the base and a fixing place for fixing the cover to the pivot.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: October 14, 2003
    Assignee: International Business Machines Corporation
    Inventors: Yoshihiro Hirasaka, Keishi Takahasi, Kohji Serizawa, Mutsuro Ohta
  • Patent number: 6594099
    Abstract: A data eraser applies a strong magnetic field to a magnetic disk while suppressing the strength of a magnetic field applied to a spindle motor. The data eraser includes an upper magnet fixer, a lower magnet fixer, and a linkage. The upper magnet fixer fixes one set of permanent magnets and the lower magnet fixer fixes another set of permanent magnets. The plate members are provided at the tips of the upper and lower magnet fixers. The plate members are made of a soft magnetic material, for example, JIS SS400, respectively. Each of these plate members functions as a yoke.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: July 15, 2003
    Assignee: International Business Machines Corporation
    Inventor: Kohji Serizawa
  • Publication number: 20020044374
    Abstract: A disk drive damper avoids matching a frequency band in which a sound frequency peak generated by the rotation of a spindle motor and a resonant frequency of the damper. The damper is attached to a disk drive apparatus and enabled to repress vibration. The damper includes a flat base portion having a jointing surface onto the disk drive apparatus and wall-thickness portions that are thicker than the flat base portion. The damper is varied in shape more freely than conventional flat dampers. Consequently, the resonant frequency of the damper can be adjusted more freely than ever.
    Type: Application
    Filed: September 19, 2001
    Publication date: April 18, 2002
    Applicant: International Business Corporation
    Inventors: Yoshihiro Hirasaka, Kohji Serizawa, Shinichi Matsuzaki, Kohji Takahashi
  • Publication number: 20020044375
    Abstract: A hard disk drive apparatus is capable of reducing a noise effectively during operation and capable of enhancing the reliability of the drive. The hard disk drive has first and second ribs that are formed near a pivot for an actuator so that a tilt of the pivot is prevented when the actuator is operated. Also, vibration absorbing members are interposed between the first and second ribs on the side of a base and a cover so that the vibration absorbing members are brought into contact with the cover. These vibration absorbing members are located in an intermediate portion between fixing places for fixing the cover to the base and a fixing place for fixing the cover to the pivot.
    Type: Application
    Filed: October 5, 2001
    Publication date: April 18, 2002
    Applicant: International Business Machines Corporation
    Inventors: Yoshihiro Hirasaka, Keishi Takahasi, Kohji Serizawa, Mutsuro Ohta
  • Publication number: 20020044376
    Abstract: A hard disk drive contains a disk assembly and a cylindrical disk container. The drive also includes a base around which a peripheral wall extends, a catching chamber including a partition wall partitioning the base into the catching chamber and a disk container, and a top cover functioning as a lid of the base. In addition, the hard disk drive has a first gasket as a first gasket section existing between the top cover and a peripheral wall of the base, and a second gasket as a second gasket section existing between the top cover and the partition wall of the catching chamber.
    Type: Application
    Filed: September 19, 2001
    Publication date: April 18, 2002
    Applicant: International Business Machines Corporation
    Inventors: Kohji Serizawa, Yoshihiro Hirasaka
  • Publication number: 20010043420
    Abstract: A data eraser applies a strong magnetic field to a magnetic disk while suppressing the strength of a magnetic field applied to a spindle motor. The data eraser includes an upper magnet fixer, a lower magnet fixer, and a linkage. The upper magnet fixer fixes one set of permanent magnets and the lower magnet fixer fixes another set of permanent magnets. The plate members are provided at the tips of the upper and lower magnet fixers. The plate members are made of a soft magnetic material, for example, JIS SS400, respectively. Each of these plate members functions as a yoke.
    Type: Application
    Filed: May 14, 2001
    Publication date: November 22, 2001
    Applicant: International Business Machines Corporation
    Inventor: Kohji Serizawa
  • Patent number: 6137658
    Abstract: An apparatus to guide and lock a rotary actuator at a limiting rotational angle in a disk storage. A rotary actuator is attached within a housing so that it is rotatable on a pivot shaft. An iron piece is rotated integrally with the rotary actuator and is attracted in magnetic cooperation with a lock magnet. A retract magnet is attached to housing and assists in rotation of the actuator during an unload operation in which the rotary actuator is removed to a load/unload ramp.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: October 24, 2000
    Assignee: International Business Machines Corporation
    Inventors: Shinichi Matsuzaki, Kohji Serizawa, Mutsuro Ohta, Keishi Takahashi
  • Patent number: 6067209
    Abstract: The present invention prevents a head/slider assembly fixed on a flexure of a head suspension assembly from having an undesired pitching motion when an unexpected excess shock is applied to a hard disk device when the head suspension is at the best position of the unload ramp.
    Type: Grant
    Filed: June 17, 1998
    Date of Patent: May 23, 2000
    Assignee: International Business Machines Corporation
    Inventors: Akihiko Aoyagi, David W. Albrecht, Kohji Serizawa, Yuhji Kobayashi, Hiroo Inoue
  • Patent number: 5818657
    Abstract: A method and system for overcoming force which inhibits movement of a data storage device are provided. The invention includes generating momentum in a moveable member and then utilizing the momentum of the moveable member to generate a large impulse force on a stationary body (e.g., the data storage device) to overcome the movement-inhibiting force thereon. This is accomplished by allowing the moveable member to move along a trajectory independently of the stationary body, thereby building momentum in the moveable member. The subsequent impact of the member on the body overcomes the force. The moveable member can then also be used, in one embodiment, to continue driving the body during system operation.
    Type: Grant
    Filed: July 31, 1996
    Date of Patent: October 6, 1998
    Assignee: International Buisness Machines Corporation
    Inventors: Sri Muthuthamby Sri-Jayantha, Vijayeshwar Das Khanna, Suresh Kumar, Mutsuro Ohta, Kohji Serizawa
  • Patent number: 5334875
    Abstract: There is a trend to increase that area of a device requiring a memory of large capacity, which is occupied by a semiconductor memory. This trend obstructs reduction of the size of the device. The present invention contemplates to provide a memory which can have a high integration, a high density and a large capacity while minimizing the mounting area. In order to achieve this memory, the TAB (Tape Automated Bonding) of the prior art is mounted on an electrically conductive connector, and a plurality of structures composed of the TAB and the connector are stacked. Moreover, the connector mounting the TAB thereon is constructed such that the independent terminals of the stacked TABs may not be shorted.
    Type: Grant
    Filed: March 2, 1993
    Date of Patent: August 2, 1994
    Assignees: Hitachi, Ltd., Hitachi Tobu Semiconductor, Ltd.
    Inventors: Toshio Sugano, Kohji Nagaoka, Seiichiro Tsukui, Yoshiaki Wakashima, Michio Tanimoto, Masayuki Watanabe, Suguru Sakaguchi, Kunihiko Nishi, Aizo Kaneda, Kohji Serizawa, Michiharu Honda, Tohru Yoshida, Takeshi Komaru, Atsushi Nakamura
  • Patent number: 5198888
    Abstract: There is a trend to increase that area of a device requiring a memory of large capacity, which is occupied by a semiconductor memory. This trend obstructs reduction of the size of the device. The present invention contemplates to provide a memory which can have a high integration, a high density and a large capacity while minimizing the mounting area. In order to achieve this memory, the TAB (Tape Automated Bonding) of the prior art is mounted on an electrically conductive connector, and a plurality of structures composed of the TAB and the connector are stacked. Moreover, the connector mounting the TAB thereon is constructed such that the independent terminals of the stacked TABs may not be shorted.
    Type: Grant
    Filed: December 20, 1990
    Date of Patent: March 30, 1993
    Assignees: Hitachi, Ltd., Hitachi Tobu Semiconductor, Ltd.
    Inventors: Toshio Sugano, Kohji Nagaoka, Seiichiro Tsukui, Yoshiaki Wakashima, Michio Tanimoto, Masayuki Watanabe, Suguru Sakaguchi, Kunihiko Nishi, Aizo Kaneda, Kohji Serizawa, Michiharu Honda, Tohru Yoshida, Takeshi Komaru, Atsushi Nakamura
  • Patent number: 5028986
    Abstract: There is a trend to increase that area of a device requiring a memory of large capacity, which is occupied by a semiconductor memory. This trend obstructs reduction of the size of the device. The present invention contemplates to provide a memory which can have a high integration, a high density and a large capacity while minimizing the mounting area. In order to achieve this memory, the TAB (Tape Automated Bonding) of the prior art is mounted on an electrically conductive connector, and a plurality of structures composed of the TAB and the connector are stacked. Moreover, the connector mounting the TAB thereon is constructed such that the independent terminals of the stacked TABs may not be shorted.
    Type: Grant
    Filed: December 23, 1988
    Date of Patent: July 2, 1991
    Assignees: Hitachi, Ltd., HitachiTobu Semiconductor, Ltd.
    Inventors: Toshio Sugano, Kohji Nagaoka, Seiichiro Tsukui, Yoshiaki Wakashima, Michio Tanimoto, Masayuki Watanabe, Suguru Sakaguchi, Kunihiko Nishi, Aizo Kaneda, Kohji Serizawa, Michiharu Honda, Tohru Yoshida, Takeshi Komaru, Atsushi Nakamura