Patents by Inventor Toshihiko Shimizu

Toshihiko Shimizu 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: 20080117726
    Abstract: An object of the invention to provide a disc autochanger without any disc reversing mechanism by using on A-side recording and reproducing apparatus and a B-side recording and reproducing apparatus while using a sheet-like optical disc in which both surfaces can be recorded and reproduced. The disc autochanger is constituted by a cartridge storing a plurality of sheet-like optical discs in which both surfaces are recorded and reproduced in a state of putting in a tray, the A-side recording and reproducing apparatus in which a moving table of an A-side recording and reproducing portion is arranged in an upper side of a tray take-out mechanism and a moving table of a cap is provided in a lower side thereof, and the B-side recording and reproducing apparatus in which a moving table of a B-side recording and reproducing portion is arranged in a lower side of the tray take-out mechanism and a moving table of a cap is provided in an upper side thereof.
    Type: Application
    Filed: April 17, 2007
    Publication date: May 22, 2008
    Inventors: Takashi Yoshida, Toshihiko Shimizu, Yukinobu Abe, Hiroyuki Awano, Yutaka Watanabe
  • Publication number: 20080112299
    Abstract: Embodiments of present invention help to realize a highly reliable magnetic disk drive by preventing a positional displacement between a magnetic head and a target track by decreasing restricting forces that a cover exerts on a base when the temperature is increased. According to one embodiment, a base is formed by aluminum die casting, has a concave, rectangular parallelepiped shape, and is formed with step portions at the four corners. A cover is a flat plate of stainless steel or iron. Four corner portions of the cover are bent to form step portions. The cover is fixed to the base at the four corners with bolts at two side positions (six positions in total). A gasket is inserted at that time to enhance the sealing performance.
    Type: Application
    Filed: November 13, 2007
    Publication date: May 15, 2008
    Applicant: Hitachi Global Storage Technologies Inc.
    Inventors: Toshihiko Shimizu, Keiko Watanabe
  • Patent number: 7348856
    Abstract: Power amplifier circuits which constitute an RF power module used for a digital device capable of handling high frequency signals in two frequency bands are disposed over the same IC chip. The power amplifier circuits are disposed around the IC chip, and a secondary circuit is disposed between the power amplifier circuits. Thus, the power amplifier circuits are provided within the same IC chip to enable a size reduction. Further, the distance between the power amplifier circuits is ensured even if the power amplifier circuits are provided within the same IC chip. It is therefore possible to suppress the coupling between the power amplifier circuits and restrain crosstalk between the power amplifier circuits.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: March 25, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Toshihiko Shimizu, Yoshikuni Matsunaga, Yuri Kusakari
  • Publication number: 20070298736
    Abstract: The RF power amplifier includes first and second amplifiers Q1 and Q2 as final-stage amplification power devices connected in parallel between an input terminal RF_In and an output terminal RF_Out. The amplifiers Q1 and Q2 are formed on one semiconductor chip. The first bias voltage Vg1 of the amplifier Q1 is set to be higher than the second bias voltage Vg2 of the amplifier Q2 so that the amplifier Q1 is operational between Class B and AB, and Q2 is operational in Class C. The first effective device size Wgq1 of the amplifier Q1 is intentionally set to be smaller than the second effective device size Wgq2 of the amplifier Q2 beyond a range of a manufacturing error of the semiconductor chip. An RF power amplifier that exhibits a high power-added efficiency characteristic regardless of whether the output power is High or Low can be materialized.
    Type: Application
    Filed: June 18, 2007
    Publication date: December 27, 2007
    Inventors: Toru FUJIOKA, Toshihiko Shimizu, Masami Ohnishi, Hidetoshi Matsumoto, Satoshi Tanaka
  • Publication number: 20070211581
    Abstract: An object of the invention is to provide a cartridge storing a plurality of sheet-shaped optical discs in a laminated manner in a state of being accommodated in trays, and a recording and reproducing apparatus of the optical disc. A cartridge stores a lot of trays in a laminated manner. The tray is formed by adhering a flat plate and a flat plate respectively having a smaller hole and a larger hole than a sheet-shaped optical disc, adhering a cover which can be opened and closed to the flat plate, and putting the optical disc in the large hole so as to be covered by the cover. The cartridge is moved up and down by a moving table, and the tray is taken out by being hooked by a hook mechanism. At this time, the cover is peeled out by a peeling claw. The optical disc is fixed to a spindle motor to which a glass disc is attached. The optical disc is rotated while being sucked to the glass disc by a fluid force, and is recorded and reproduced by a recording and reproducing portion.
    Type: Application
    Filed: December 20, 2006
    Publication date: September 13, 2007
    Applicant: HITACHI MAXELL, LTD.
    Inventors: Takashi Yoshida, Toshihiko Shimizu, Kazushi Yoshida, Taichirou Yamashita
  • Patent number: 7215203
    Abstract: A multistage high frequency power amplifier-circuit device has a plurality of semiconductor amplification elements connected in a cascade. The circuit device is provided with a bias control circuit used to control the bias voltage or bias current of the output semiconductor amplification element in each stage so as to reduce the variation of the output power with respect to the power control signal voltage in an area around the threshold voltage of the semiconductor amplification elements. This realizes a high frequency power amplifier circuit device provided with excellent controllability of the output power and high efficiency at the time of low power output realized with use of such a control voltage as a power control signal.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: May 8, 2007
    Assignees: Renesas Technology Corp., Hitachi Communication Systems, Inc.
    Inventors: Yoshikuni Matsunaga, Toshihiko Shimizu, Tomio Furuya, Nobuhiro Matsudaira, Koichi Matsushita
  • Publication number: 20070041129
    Abstract: A head support mechanism includes a head to read/write information, and an actuator for moving the head. Flanges are provided on opposite sides of a load beam of the head support mechanism, and at least one recessed portion is provided on the load beam. A thickness of the load beam at the at least one recessed portion is smaller than a thickness at other portions of the load beam at least one of oscillation damping material and an IC circuit is arranged in the at least one recessed portion.
    Type: Application
    Filed: October 27, 2006
    Publication date: February 22, 2007
    Inventors: Toshihiko Shimizu, Hiromitsu Masuda, Irizo Naniwa, Mikio Tokuyama, Shigeo Nakamura, Kousaku Wakatsuki, Haruhide Takahashi, Masaki Odai
  • Publication number: 20070002497
    Abstract: A carriage includes a slider on which a magnetic head for reading/writing information from/to a disk is mounted, a suspension for carrying the slider and for applying a predetermined load to the slider, a carriage arm to which the suspension is attached, and a body section to which the carriage arm is connected. The carriage arm includes a suspension fixing portion, as arm arranged substantially in parallel with a disk surface, and a restricting member which is a thin-plate-like member having a surface which is opposite to the plane of arm which is parallel to the disk surface. The restricting member and the arm are coupled via a viscoelastic body.
    Type: Application
    Filed: September 7, 2006
    Publication date: January 4, 2007
    Inventors: Toshihiko Shimizu, Tetsuya Hamaguchi, Toshihiro Arisaka, Hiromitsu Masuda, Gentaro Nakamura, Takenori Atsumi
  • Publication number: 20060290431
    Abstract: Power amplifier circuits which constitute an RF power module used for a digital device capable of handling high frequency signals in two frequency bands are disposed over the same IC chip. The power amplifier circuits are disposed around the IC chip, and a secondary circuit is disposed between the power amplifier circuits. Thus, the power amplifier circuits are provided within the same IC chip to enable a size reduction. Further, the distance between the power amplifier circuits is ensured even if the power amplifier circuits are provided within the same IC chip. It is therefore possible to suppress the coupling between the power amplifier circuits and restrain crosstalk between the power amplifier circuits.
    Type: Application
    Filed: August 17, 2006
    Publication date: December 28, 2006
    Inventors: Toshihiko Shimizu, Yoshikuni Matsunaga, Yuri Kusakari
  • Patent number: 7130159
    Abstract: A head support mechanism includes a head to write/read information, and a head support member to support the head. The head support member has parts delimiting an opening at a portion thereof in which opposing parts which delimit the opening in a width direction of the head support member are elastically deformable. Protrusions are formed on edges of the opening, and piezoelectric elements are mounted on the protrusions to enable deforming of the head support member in a direction of positioning of the head.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: October 31, 2006
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Toshihiko Shimizu, Hiromitsu Masuda, Irizo Naniwa, Mikio Tokuyama, Shigeo Nakamura, Kousaku Wakatsuki, Haruhide Takahashi, Masaki Odai
  • Patent number: 7116175
    Abstract: Power amplifier circuits which constitute an RF power module used for a digital device capable of handling high frequency signals in two frequency bands are disposed over the same IC chip. The power amplifier circuits are disposed around the IC chip, and a secondary circuit is disposed between the power amplifier circuits. Thus, the power amplifier circuits are provided within the same IC chip to enable a size reduction. Further, the distance between the power amplifier circuits is ensured even if the power amplifier circuits are provided within the same IC chip. It is therefore possible to suppress the coupling between the power amplifier circuits and restrain crosstalk between the power amplifier circuits.
    Type: Grant
    Filed: July 14, 2004
    Date of Patent: October 3, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Toshihiko Shimizu, Yoshikuni Matsunaga, Yuri Kusakari
  • Patent number: 7110223
    Abstract: A carriage for a magnetic disk apparatus includes a slider on which a magnetic head for reading/writing information from/to a disk is mounted, a suspension for carrying the slider and for applying a predetermined load to the slider, and a carriage arm to which the suspension is attached. The carriage arm includes a suspension fixing portion, first and second arms arranged substantially in parallel with a disk surface, and a restricting member having a surface opposite to the first and second arms. The restricting member and the first arm, and the restricting member and the second arm are coupled via a viscoelastic body.
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: September 19, 2006
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Toshihiko Shimizu, Tetsuya Hamaguchi, Toshihiro Arisaka, Hiromitsu Masuda, Gentaro Nakamura, Takenori Atsumi
  • Publication number: 20060197600
    Abstract: A multistage high frequency power amplifier-circuit device has a plurality of semiconductor amplification elements connected in a cascade. The circuit device is provided with a bias control circuit used to control the bias voltage or bias current of the output semiconductor amplification element in each stage so as to reduce the variation of the output power with respect to the power control signal voltage in an area around the threshold voltage of the semiconductor amplification elements. This realizes a high frequency power amplifier circuit device provided with excellent controllability of the output power and high efficiency at the time of low power output realized with use of such a control voltage as a power control signal.
    Type: Application
    Filed: May 1, 2006
    Publication date: September 7, 2006
    Inventors: Yoshikuni Matsunaga, Toshihiko Shimizu, Tomio Furuya, Nobuhiro Matsudaira, Koichi Matsushita
  • Publication number: 20060158786
    Abstract: A carriage for a magnetic disk apparatus includes a slider on which a magnetic head for reading/writing information from/to a disk is mounted, a suspension for carrying the slider and for applying a predetermined load to the slider, and a carriage arm to which the suspension is attached. The carriage arm includes a suspension fixing portion, first and second arms arranged substantially in parallel with a disk surface, and a restricting member having a surface opposite to the first and second arms. The restricting member and the first arm, and the restricting member and the second arm are coupled via a viscoelastic body.
    Type: Application
    Filed: March 15, 2006
    Publication date: July 20, 2006
    Inventors: Toshihiko Shimizu, Tetsuya Hamaguchi, Toshihiro Arisaka, Hiromitsu Masuda, Gentaro Nakamura, Takenori Atsumi
  • Patent number: 7061722
    Abstract: A magnetic disk unit includes a magnetic disk attached to a spindle so as to be rotatable, a slider having a magnetic head for reading/writing data onto/from the magnetic disk, a suspension for providing the slider with a predetermined load, and an actuator arm for positioning the slider attached to the suspension on the magnetic disk. A first pad including the magnetic head and second pads including no magnetic heads are disposed on an air bearing surface of the slider. During rotation of said magnetic disk, a part of the first pad keeps in contact with the magnetic disk. A load point of the suspension with respect to the slider is positioned between a leading edge of the slider and a position located at a distance equivalent to substantially 0.42 times a whole length of the slider from the leading edge of the slider.
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: June 13, 2006
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Hidekazu Kohira, Hiromitsu Tokisue, Masaaki Matsumoto, Masayuki Suzuki, Yoshinori Takeuchi, Toshihiko Shimizu
  • Patent number: 7049892
    Abstract: A multistage high frequency power amplifier circuit device has a plurality of semiconductor amplification elements connected in a cascade. The circuit device is provided with a bias control circuit used to control the bias voltage or bias current of the output semiconductor amplification element in each stage so as to reduce the variation of the output power with respect to the power control signal voltage in an area around the threshold voltage of the semiconductor amplification elements. This realizes a high frequency power amplifier circuit device provided with excellent controllability of the output power and high efficiency at the time of low power output realized with use of such a control voltage as a power control signal.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: May 23, 2006
    Assignees: Renesas Technology Corp., Hitachi Communications Systems, Inc.
    Inventors: Yoshikuni Matsunaga, Toshihiko Shimizu, Tomio Furuya, Nobuhiro Matsudaira, Koichi Matsushita
  • Patent number: 7031118
    Abstract: A carriage arm assembly for swingably supporting a magnetic head which includes a slider, a suspension carrying the slider, a carriage arm to which the suspension is attached, and a body section. The carriage arm extends from the body section and includes first and second arm members extending substantially in parallel with a swinging plane of the carriage arm, and a fixing portion provided at a distal end of the carriage arm for mounting the suspension thereon. Each of the first and second arm members have narrow sections in a distal end area and a base end area thereof, wherein a width of the narrow sections in a swinging direction is smaller than a width of an intermediate area of the first and second arm members.
    Type: Grant
    Filed: April 6, 2005
    Date of Patent: April 18, 2006
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Toshihiko Shimizu, Tetsuya Hamaguchi, Toshihiro Arisaka, Hiromitsu Masuda, Gentaro Nakamura, Takenori Atsumi
  • Publication number: 20060072240
    Abstract: Embodiments of the invention provide a magnetic disk device capable of improving the shielding function for the magnetic head yet maintaining a form factor. In one embodiment, a magnetic disk device comprises a magnetic disk; a magnetic head for recording/reproducing information; a magnetic disk drive mechanism for moving magnetic head in the radial direction of the magnetic disk; a housing including a base and a cover having a nonmagnetic material; and a magnetic shielding member having a magnetic material. The housing has a cut-away portion corresponding to a range in which the magnetic head moves, and the magnetic shielding member is formed in a U-shape including an upper wall portion, a side wall portion and a bottom wall portion. The magnetic shielding member covers the range in which the magnetic head moves, and is disposed in the cut-away portion so as to form substantially the same surface as the surfaces of the upper wall, side wall and bottom wall of the housing.
    Type: Application
    Filed: September 30, 2005
    Publication date: April 6, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Takehiko Eguchi, Toshihiko Shimizu, Mikio Tokuyama
  • Publication number: 20060056104
    Abstract: Embodiments of the invention provide a magnetic disk device which improves the shielding function for the magnetic heads yet maintaining a form factor relying upon an inexpensive constitution. In one embodiment, a magnetic disk device comprises a rotary disk-type magnetic disk; a magnetic head for recording or reproducing information; a magnetic head support mechanism for supporting the magnetic head; a shroud having an opening in which the magnetic head support mechanism is inserted, and surrounding the outer circumference of the magnetic disk; and a housing. The housing includes a base and a cover, and accommodates the magnetic disk, the magnetic head, the magnetic head support mechanism and the shroud. The base is constituted by using a nonmagnetic material and the shroud is constituted by using a magnetic material.
    Type: Application
    Filed: September 9, 2005
    Publication date: March 16, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Takehiko Eguchi, Masayuki Kurita, Toshihiko Shimizu, Mikio Tokuyama
  • Publication number: 20060056105
    Abstract: In a magnetic disk apparatus, a function of shielding a magnetic head is improved while maintaining the form factor with an inexpensive structure. In one embodiment, a magnetic disk apparatus has a magnetic disk, a magnetic head that records or plays back information, a magnetic head support mechanism supporting the magnetic head, a positioning mechanism that moves the magnetic head in a radial direction of the magnetic disk to place the head in position, an enclosure made of a nonmagnetic material, and a shield member made of a magnetic material. The magnetic disk, magnetic head, magnetic head support mechanism, positioning mechanism, and shield member are housed in the enclosure.
    Type: Application
    Filed: September 9, 2005
    Publication date: March 16, 2006
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Takehiko Eguchi, Toshihiko Shimizu, Toshiya Shiramatsu, Mikio Tokuyama