Patents by Inventor Masao Iwakura

Masao Iwakura 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: 7925028
    Abstract: An electronic device having a first motor which rotates a rotating body (for example, blades) about a rotation axis and a second motor which vibrates a vibrator including the rotating body in the axial direction is provided. A control IC unit has a first circuit which subjects the rotation to control drive by a first waveform, and a second circuit which subjects the vibration to control drive by a second waveform. Rotation and vibration of a rotating and vibrating unit driven by the first and second motors generates an airflow and output sound by a synthesized output of a first output corresponding to the rotation and a second output corresponding to the vibration. The control IC unit generates a second waveform by using a reversed-phase waveform with respect to the first waveform or the like and suppresses the output sound by control of the first and second waveforms.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: April 12, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Nobuhiro Yokoyama, Takashi Chikusa, Masao Iwakura
  • Patent number: 7733599
    Abstract: Embodiments of the invention provide a magnetic disk unit in which there has been adopted a structure fixing a base and a top plate and preventing a deformation by a bimetal effect. In one embodiment, the magnetic disk unit includes a magnetic disk; a head drive mechanism in which is mounted a head accessing the magnetic disk; a base accommodating the magnetic disk and the head drive mechanism, and possessing a flat part, in which a threaded hole has been formed, in a circumference of an opening edge; and a top cover which is formed by a material whose thermal expansion coefficient differs from that of the base, in which there is provided an escape hole, for a screw, position-aligned to the threaded hole of the flat part, and which is attached to the base by the screw penetrating through the threaded hole and the escape hole for the screw.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: June 8, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hiroaki Shigenaga, Sunao Yonekawa, Masao Iwakura, Masami Miyatake
  • Publication number: 20090129936
    Abstract: An electronic device having a first motor which rotates a rotating body (for example, blades) about a rotation axis and a second motor which vibrates a vibrator including the rotating body in the axial direction is provided. A control IC unit has a first circuit which subjects the rotation to control drive by a first waveform, and a second circuit which subjects the vibration to control drive by a second waveform. Rotation and vibration of a rotating and vibrating unit driven by the first and second motors generates an airflow and output sound by a synthesized output of a first output corresponding to the rotation and a second output corresponding to the vibration. The control IC unit generates a second waveform by using a reversed-phase waveform with respect to the first waveform or the like and suppresses the output sound by control of the first and second waveforms.
    Type: Application
    Filed: February 6, 2008
    Publication date: May 21, 2009
    Inventors: Nobuhiro YOKOYAMA, Takashi Chikusa, Masao Iwakura
  • Patent number: 7330334
    Abstract: A magnetic disk apparatus includes a plurality of magnetic disks driven to rotate by a spindle motor, arms supporting magnetic heads on the magnetic disks, an actuator for moving the arms on the magnetic disks by a voice coil motor, and a housing which surrounds the magnetic disks, the arms and the actuator. A shroud which arcuately surrounds the magnetic disks along the outer periphery thereof has an opened portion for inserting the arms is formed in a part of the housing. The shroud on an upstream side of the arms relative to airflow generated by the magnetic disks when rotating is provided with an opening having a greater width than that of a gap defined between the shroud and the outer periphery of the magnetic disks. An empty bypass channel is provided which communicates from the opening through a rear side of the voice coil motor to the downstream side of the arms.
    Type: Grant
    Filed: May 16, 2005
    Date of Patent: February 12, 2008
    Assignee: Hitachi Global Storage Technologies Japan, 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
  • Publication number: 20070047130
    Abstract: Embodiments of the invention provide a magnetic disk unit in which there has been adopted a structure fixing a base and a top plate and preventing a deformation by a bimetal effect. In one embodiment, the magnetic disk unit includes a magnetic disk; a head drive mechanism in which is mounted a head accessing the magnetic disk; a base accommodating the magnetic disk and the head drive mechanism, and possessing a flat part, in which a threaded hole has been formed, in a circumference of an opening edge; and a top cover which is formed by a material whose thermal expansion coefficient differs from that of the base, in which there is provided an escape hole, for a screw, position-aligned to the threaded hole of the flat part, and which is attached to the base by the screw penetrating through the threaded hole and the escape hole for the screw.
    Type: Application
    Filed: August 3, 2006
    Publication date: March 1, 2007
    Applicant: Hitachi Global Storage Technologies
    Inventors: Hiroaki Shigenaga, Sunao Yonekawa, Masao Iwakura, Masami Miyatake
  • Publication number: 20050219741
    Abstract: A magnetic disk apparatus includes a plurality of magnetic disks driven to rotate by a spindle motor, arms supporting magnetic heads on the magnetic disks, an actuator for moving the arms on the magnetic disks by a voice coil motor, and a housing which surrounds the magnetic disks, the arms and the actuator. A shroud which arcuately surrounds the magnetic disks along the outer periphery thereof has an opened portion for inserting the arms is formed in a part of the housing. The shroud on an upstream side of the arms relative to airflow generated by the magnetic disks when rotating is provided with an opening having a greater width than that of a gap defined between the shroud and the outer periphery of the magnetic disks. An empty bypass channel is provided which communicates from the opening through a rear side of the voice coil motor to the downstream side of the arms.
    Type: Application
    Filed: May 16, 2005
    Publication date: October 6, 2005
    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: 6898049
    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: Grant
    Filed: April 9, 2003
    Date of Patent: May 24, 2005
    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: 6728074
    Abstract: In a latch release apparatus and method, a latch mechanism holds an actuator with a high shock resistance. Two or more magnetic members are arranged in a latch component so as to concentrate a magnetic force for easy rotation of the latch component. The effect of the magnetic force in a direction perpendicular to the direction of rotation of the magnetic members becomes smaller, reducing the friction force at the rotational center of the latch.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: April 27, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyoshi Hanada, Masao Iwakura, Yasuyuki Hozumi, Kazumi Fujimoto
  • Patent number: 6717774
    Abstract: In a latch mechanism that holds an actuator with a high shock resistance two or more magnetic members are arranged in a latch component, which generates a weaker attraction force but a more easy rotation of the latch component. The structure concentrates a magnetic force in order to rotate the latch component effectively. The effect of the magnetic force in a direction perpendicular to the direction of rotation of the magnetic members becomes smaller and a friction force at the rotation center of the latch is reduced.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: April 6, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyoshi Hanada, Masao Iwakura, Yasuyuki Hozumi, Kazumi Fujimoto
  • Patent number: 6665139
    Abstract: In a magnetic disc apparatus including a plurality of magnetic discs 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 discs are larger than 0.1 mm and less than 0.6 mm. An open space is located, downstream of the arms with respect to the air flow on surfaces of the magnetic discs, 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 discs and the shroud, and a bypass channel is provided which communicates between the opening and open space.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: December 16, 2003
    Assignee: Hitachi, Ltd.
    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
  • 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
  • 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
  • Patent number: 6490123
    Abstract: A magnetic disk drive has a housing for a 3.5 inch form factor and disk media of a diameter for a 2.5 inch form factor. The smaller disk media rotate at a high speed while consuming low electric lower and generating less heat while providing for quick access speeds. Usually, when the magnetic disk media are rotated at a higher speed, the electric power consumption and heat generation are increased because of the load increase. This problem is avoided with the use of cooling fins placed about the periphery of the disk media. Further, the smaller size disk media enable a decrease in torque loss during on-load rotation with the media, and a decrease of electric current to the spindle motor during rotation.
    Type: Grant
    Filed: November 5, 1998
    Date of Patent: December 3, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Nobuyuki Okunaga, Masao Iwakura, Kazuo Nakagoshi, Takuji Ogawa, Chuma Akira, Fumio Kugiya, Tomio Suzuki, Toshiaki Kojima, Kazuo Sakai, Naoki Kodama, Tatsuya Ishigaki
  • Publication number: 20020093758
    Abstract: A magnetic disk drive that shape coefficient is 3.5 inches are provided, which is designed as rotating magnetic media in a high speed in order to consume a low electric power, to generate a less heat, and to access more quickly.
    Type: Application
    Filed: March 8, 2002
    Publication date: July 18, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Nobuyuki Okunaga, Masao Iwakura, Kazuo Nakagoshi, Takuji Ogawa, Chuma Akira, Fumio Kugiya, Tomio Suzuki, Toshiaki Kojima, Kazuo Sakai, Naoki Kodama, Tatsuya Ishigaki
  • Publication number: 20020093760
    Abstract: A magnetic disk drive that shape coefficient is 3.5 inches are provided, which is designed as rotating magnetic media in a high speed in order to consume a low electric power, to generate a less heat, and to access more quickly.
    Type: Application
    Filed: March 8, 2002
    Publication date: July 18, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Nobuyuki Okunaga, Masao Iwakura, Kazuo Nakagoshi, Takuji Ogawa, Chuma Akira, Fumio Kugiya, Tomio Suzuki, Toshiaki Kojima, Kazuo Sakai, Naoki Kodama, Tatsuya Ishigaki
  • Publication number: 20020093759
    Abstract: A magnetic disk drive that shape coefficient is 3.5 inches are provided, which is designed as rotating magnetic media in a high speed in order to consume a low electric power, to generate a less heat, and to access more quickly.
    Type: Application
    Filed: March 8, 2002
    Publication date: July 18, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Nobuyuki Okunaga, Masao Iwakura, Kazuo Nakagoshi, Takuji Ogawa, Chuma Akira, Fumio Kugiya, Tomio Suzuki, Toshiaki Kojima, Kazuo Sakai, Naoki Kodama, Tatsuya Ishigaki
  • Publication number: 20020080528
    Abstract: A latch mechanism that holds an actuator with a high shock resistance is provided, whilst endeavoring to achieve a small, high-capacity apparatus, high-density recording, a constitution with high component density, low costs, and low consumption of electrical power.
    Type: Application
    Filed: September 20, 2001
    Publication date: June 27, 2002
    Inventors: Kazuyoshi Hanada, Masao Iwakura, Yasuyuki Hozumi, Kazumi Fujimoto
  • 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
  • Publication number: 20020075603
    Abstract: A latch mechanism that holds an actuator with a high shock resistance is provided, whilst endeavoring to achieve a small, high-capacity apparatus, high-density recording, a constitution with high component density, low costs, and low consumption of electrical power.
    Type: Application
    Filed: September 20, 2001
    Publication date: June 20, 2002
    Inventors: Kazuyoshi Hanada, Masao Iwakura, Yasuyuki Hozumi, Kazumi Fujimoto