Patents by Inventor Keiichi Kohno

Keiichi Kohno 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: 5956200
    Abstract: Disclosed are a method of and an apparatus for controlling a magnetic disc drive including a magnetic head in which a write head and a read head are separated. The control method comprises: a step of calculating a moving quantity up to a designated target track position in accordance with a write instruction or a read instruction and calculating a moving quantity from the moving quantity up to the target track position and a yaw angle offset quantity in accordance with the read instruction or the write instruction; and a step of locating the magnetic head in the target track position by seek-controlling the rotary type actuator in accordance with the calculated moving quantity.
    Type: Grant
    Filed: March 1, 1996
    Date of Patent: September 21, 1999
    Assignee: Fujitsu Limited
    Inventors: Keiichi Kohno, Tsuyoshi Takahashi, Masayoshi Ishii, Yoshiyuki Nagasaka, Tamotsu Kozuka, Susumu Yoshida
  • Patent number: 5831782
    Abstract: Disclosed are a method of and an apparatus for controlling a magnetic disc drive including a magnetic head in which a write head and a read head are separated. The control method comprises: a step of calculating a moving quantity up to a designated target track position in accordance with a write instruction or a read instruction and calculating a moving quantity from the moving quantity up to the target track position and a yaw angle offset quantity in accordance with the read instruction or the write instruction; and a step of locating the magnetic head in the target track position by seek-controlling the rotary type actuator in accordance with the calculated moving quantity.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: November 3, 1998
    Assignee: Fujitsu Limited
    Inventors: Keiichi Kohno, Tsuyoshi Takahashi, Masayoshi Ishii, Yoshiyuki Nagasaka, Tamotsu Kozuka, Susumu Yoshida
  • Patent number: 5193146
    Abstract: A pulse width modulation (PWM) control system for rotating a spindle motor and a rotatable recording medium at a constant speed.
    Type: Grant
    Filed: August 20, 1990
    Date of Patent: March 9, 1993
    Assignee: Fujitsu Limited
    Inventor: Keiichi Kohno
  • Patent number: 4966899
    Abstract: An antibacterial lyophilized preparation which comprises as an active ingredient aspoxicillin and a basic salt of aspoxicillin in a molar ratio of 1 : about 0.7 to 7 and optionally an alkali metal halide as a stabilizer, and a method for preparing the same, said antibacterial lyophilized preparation being able to be rapidly dissolved in distilled water to give a stable solution which can be injected to patients for the treatment of various bacterial infectious diseases.
    Type: Grant
    Filed: January 14, 1988
    Date of Patent: October 30, 1990
    Assignee: Tanabe Seiyaku Co., Ltd.
    Inventors: Keiichi Kohno, Hiroshi Miura, Yoshiyuki Hirakawa, Toshiyuki Ueki, Seiichi Morikuni
  • Patent number: 4924165
    Abstract: In a servo control system having a coarse control unit and a fine control unit, a differential gain is changed temporarily during a short period at an initial state of fine control to shorten a settling time and to reduce overshoot. The servo control system includes a controlled system including a controlled object and a drive unit, a unit for controlling a speed of the controlled object to move and position the same to or adjacent a reference position, and a unit having a differential control circuit and for controlling a position of the controlled object to position the controlled object to the reference position, after the speed control unit moves the controlled object to or adjacent to the reference position. A differential gain of the differential control circuit is selected from at least two values, a first of which is used at an initial state and a second of which is used after the initial state. The servo control system is applicable to a disc system, a printer, etc.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: May 8, 1990
    Assignee: Fujitsu Limited
    Inventor: Keiichi Kohno
  • Patent number: 4897743
    Abstract: Releasing adhesion between a magnetic head and a magnetic disk by radially moving the head before the disk begins to rotate. The head movement is accomplished by compressing an elastic stopper means by driving a head actuator motor with drive current so that unwanted vibration of bounce back of the head is prevented.
    Type: Grant
    Filed: August 18, 1987
    Date of Patent: January 30, 1990
    Assignee: Fujitsu Limited
    Inventor: Keiichi Kohno