Patents by Inventor Kentaroh Katoh

Kentaroh Katoh 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).

  • Magnetic disk apparatus and method for monitoring high-frequency oscillation components
    Patent number: 7102843
    Abstract: A magnetic disk apparatus includes a magnetic disk with normal and double servo sectors arranged alternately. If a servo interruption period corresponding to adjacent first servo sectors is a first servo interruption period, then a second servo interruption period that is a servo interruption period corresponding to adjacent first servo sector and second servo sector is equal to or less than half of the first servo interruption period.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: September 5, 2006
    Assignee: Fujitsu Limited
    Inventors: Takeshi Hara, Mitsuo Kamimura, Yukio Abe, Yoshinari Higashino, Kunihiro Shimada, Kiyoshi Sakuma, Atsushi Suzuki, Kentaroh Katoh
  • Controller circuit connectable to an actuator designed to position a head in a recording medium drive according to a filtered positioning control signal
    Patent number: 6798604
    Abstract: The controller circuit is designed to generate the positioning control signal based on the positional deviation of the head from a target recording track on a recording medium. A feedback control is effected to position the head right on a trajectory corresponding to the target recording track based on the generated positioning control signal. The positioning control signal is subjected to filtering at a notch filter. The cutoff frequency of the notch filter is set depending on the temperature detected at a thermal sensor. Even when the resonant frequency shifts in response to variation in temperature, the cutoff frequency of the notch filter follows the shift of the resonant frequency. A narrower bandwidth of the cutoff frequency still achieves reduction in the amplitude of the frequency component corresponding to the resonant frequency. The resonance or continuous vibration can reliably be prevented in the head.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: September 28, 2004
    Assignee: Fujitsu Limited
    Inventors: Mitsuo Kamimura, Yoshinari Higashino, Kiyoshi Sakuma, Yukio Abe, Kunihiro Shimada, Atsushi Suzuki, Takeshi Hara, Kentaroh Katoh
  • Magnetic disk apparatus and method for monitoring high-frequency oscillation components
    Publication number: 20040125494
    Abstract: A magnetic disk apparatus includes a magnetic disk with normal and double servo sectors arranged alternately. If a servo interruption period corresponding to adjacent first servo sectors is a first servo interruption period, then a second servo interruption period that is a servo interruption period corresponding to adjacent first servo sector and second servo sector is equal to or less than half of the first servo interruption period.
    Type: Application
    Filed: October 27, 2003
    Publication date: July 1, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Takeshi Hara, Mitsuo Kamimura, Yukio Abe, Yoshinari Higashino, Kunihiro Shimada, Kiyoshi Sakuma, Atsushi Suzuki, Kentaroh Katoh