Patents by Inventor Kenji Toga

Kenji Toga 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: 8132459
    Abstract: Systems and methods are provided for determining mechanical resonance of a sensor. In one embodiment, a system is provided that comprises a bias voltage source configured to apply a bias voltage impulse signal to a terminal of the sensor and a zero crossing detector configured to detect zero crossing cycles of a sensor output signal response to the bias voltage impulse signal. The system further comprises a controller configured to determine the resonance frequency of the sensor based on the detected zero crossing cycles of the sensor output signal response.
    Type: Grant
    Filed: September 13, 2008
    Date of Patent: March 13, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Kenji Toga, Masaki Yamahsita
  • Publication number: 20100064809
    Abstract: Systems and methods are provided for determining mechanical resonance of a sensor. In one embodiment, a system is provided that comprises a bias voltage source configured to apply a bias voltage impulse signal to a terminal of the sensor and a zero crossing detector configured to detect zero crossing cycles of a sensor output signal response to the bias voltage impulse signal. The system further comprises a controller configured to determine the resonance frequency of the sensor based on the detected zero crossing cycles of the sensor output signal response.
    Type: Application
    Filed: September 13, 2008
    Publication date: March 18, 2010
    Inventors: Kenji Toga, Masaki Yamashita
  • Patent number: 7408732
    Abstract: An information recording method in a rotating storage apparatus comprising a rotating recording medium for recording information, a head for performing at least a write operation onto the rotating recording medium, and an acceleration sensor for detecting a shock. The method comprises outputting a shock out signal if an output from the acceleration sensor exceeds a predetermined threshold. A signal is output at a first level for a write inhibit period in response to the input of the shock out signal, where the write inhibit period is selected based at least in part on a time span in which the output of the acceleration sensor exceeds the predetermined threshold. Writing to the rotating recording medium is prohibited during the write inhibit period.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: August 5, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Publication number: 20060077587
    Abstract: An information recording method in a rotating storage apparatus comprising a rotating recording medium for recording information, a head for performing at least a write operation onto the rotating recording medium, and an acceleration sensor for detecting a shock. The method comprises outputting a shock out signal if an output from the acceleration sensor exceeds a predetermined threshold. A signal is output at a first level during a write inhibit period in response to the input of the shock out signal, where the write inhibit period is selected based at least in part on a time span in which the output of the acceleration sensor exceeds the predetermined threshold. Writing to the rotating recording medium is prohibited during the write inhibit period.
    Type: Application
    Filed: November 29, 2005
    Publication date: April 13, 2006
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Patent number: 7002766
    Abstract: A rotating storage apparatus is provided for high recording reliability in an environment in which a shock or vibration exists. Provided are means for outputting a shock out signal (SO) if an output from an acceleration sensor exceeds a predetermined threshold, a latch circuit 21 for outputting a latch signal at high level during a predetermined write inhibit period after the shock out signal (SO) is input, and a write gate signal (WG) which goes high when a write is enabled. A write enable signal is generated by an AND circuit 23 having a NOT output of the latch signal as well as the write gate signal WO as its inputs.
    Type: Grant
    Filed: March 3, 2004
    Date of Patent: February 21, 2006
    Assignee: Hitachi Global Technologies Netherlands, B.V.
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Publication number: 20040190187
    Abstract: A rotating storage apparatus is provided for high recording reliability in an environment in which a shock or vibration exists. Provided are means for outputting a shock out signal (SO) if an output from an acceleration sensor exceeds a predetermined threshold, a latch circuit 21 for outputting a latch signal at high level during a predetermined write inhibit period after the shock out signal (SO) is input, and a write gate signal (WG) which goes high when a write is enabled. A write enable signal is generated by an AND circuit 23 having a NOT output of the latch signal as well as the write gate signal WO as its inputs.
    Type: Application
    Filed: March 3, 2004
    Publication date: September 30, 2004
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Patent number: 6754021
    Abstract: A rotating storage apparatus is provided for high recording reliability in an environment in which a shock or vibration exists. Provided are means for outputting a shock out signal (SO) if an output from an acceleration sensor exceeds a predetermined threshold, a latch circuit 21 for outputting a latch signal at high level during a predetermined write inhibit period after the shock out signal (SO) is input, and a write gate signal (WG) which goes high when a write is enabled. A write enable signal is generated by an AND circuit 23 having a NOT output of the latch signal as well as the write gate signal WG as its inputs.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: June 22, 2004
    Assignee: International Business Machines Corporation
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Patent number: 6747832
    Abstract: A disk drive has a data recording medium such as a disk, a spindle motor for rotating the disk, disk rotation speed controlling logics for supplying a spindle current to the above described spindle motor to rotate the disk at a constant speed, a head unit for accessing the disk, an actuator for moving the head unit, and head position controlling logics for driving the actuator and controlling the position of the head unit. The head position controlling logic obtains the value of the spindle current and controls the position of the head unit on the basis of the above described spindle current value by using the fact that the spindle current varies according to variations in the position of the head unit.
    Type: Grant
    Filed: March 27, 2001
    Date of Patent: June 8, 2004
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Publication number: 20020141097
    Abstract: A disk drive has a data recording medium such as a disk, a spindle motor for rotating the disk, disk rotation speed controlling logics for supplying a spindle current to the above described spindle motor to rotate the disk at a constant speed, a head unit for accessing the disk, an actuator for moving the head unit, and head position controlling logics for driving the actuator and controlling the position of the head unit.
    Type: Application
    Filed: March 27, 2001
    Publication date: October 3, 2002
    Applicant: International Business Machines Corporation
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Publication number: 20010026413
    Abstract: A rotating storage apparatus is provided for high recording reliability in an environment in which a shock or vibration exists. Provided are means for outputting a shock out signal (SO) if an output from an acceleration sensor exceeds a predetermined threshold, a latch circuit 21 for outputting a latch signal at high level during a predetermined write inhibit period after the shock out signal (SO) is input, and a write gate signal (WG) which goes high when a write is enabled. A write enable signal is generated by an AND circuit 23 having a NOT output of the latch signal as well as the write gate signal WG as its inputs.
    Type: Application
    Filed: March 19, 2001
    Publication date: October 4, 2001
    Inventors: Masashi Kisaka, Yutaka Ozawa, Kenji Toga
  • Patent number: 5994866
    Abstract: A motor having enhanced transient characteristics during the acceleration time of the motor in a disk unit. The motor includes a motor controller having a phase-locked loop (PLL) or frequency-locked loop (FLL) for controlling the speed of a spindle motor in a disk drive. The PLL or FLL is coupled to a digital filter. The difference between a phase or frequency synchronized with the rotational speed of the motor and a target value is received by the digital filter. The digital filter output is added to the target value. The sum of the filter output and the target value is set in the PLL or FLL as an adjusted target value to perform PLL control or FLL control. With this arrangement, the time to shift from a low-speed rotation state to a high-speed rotation state can be shortened.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: November 30, 1999
    Assignee: International Business Machines Corporation
    Inventors: Masashi Kisaka, Kenji Toga, Hiroshi Uchiike