Patents by Inventor Tatsuya Gofuku

Tatsuya Gofuku 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: 6501609
    Abstract: An actuator driving method and an actuator driving device for PWM-driving an actuator of a storage disk device are disclosed. This method and device prevent a servo signal from being overlapped with switching noises. The storage disk device includes a head for reading information from a storage disk, a PWM driver for generating a drive current having a pulse width corresponding to a current indication value, a linear driver for generating a drive current of which a magnitude corresponds to the current indication value, an actuator, driven by the drive current, for moving the head, and a control circuit for generating the current indication value for positioning the head from the servo information read by the head from the storage disk. The driving method includes a step of PWM-driving the actuator by the PWM driver, and a step of effecting a switchover from the PWM drive to a linear drive by the linear driver during a period for which the control circuit reads the servo information.
    Type: Grant
    Filed: December 7, 1998
    Date of Patent: December 31, 2002
    Assignee: Fujitsu Limited
    Inventors: Tomoaki Saito, Tatsuya Gofuku
  • Publication number: 20010043429
    Abstract: An actuator driving method and an actuator driving device for PWM-driving an actuator of a storage disk device are disclosed. This method and device prevent a servo signal from being overlapped with switching noises. The storage disk device includes a head for reading information from a storage disk, a PWM driver for generating a drive current having a pulse width corresponding to a current indication value, a linear driver for generating a drive current of which a magnitude corresponds to the current indication value, an actuator, driven by the drive current, for moving the head, and a control circuit for generating the current indication value for positioning the head from the servo information read by the head from the storage disk. The driving method includes a step of PWM-driving the actuator by the PWM driver, and a step of effecting a switchover from the PWM drive to a linear drive by the linear driver during a period for which the control circuit reads the servo information.
    Type: Application
    Filed: December 7, 1998
    Publication date: November 22, 2001
    Inventors: TOMOAKI SAITO, TATSUYA GOFUKU
  • Publication number: 20010013989
    Abstract: For a balance adjustment due to a reduction in size and weight of an actuator, an arm portion, an axis attaching portion, and a coil supporting portion are arranged so that the centers of gravity on the coil side are located on a straight line connecting a rotational center and the center of gravity on the head side. Further, the improvement of an assembling efficiency of a VCM, an increase in torque, a one-touch fixing of an FPC connecting band, a noise prevention of a read pattern, and an insulation between the base and cover due to a bias of an MR read head are accomplished. A sector mark is detected by comparing a peak detection pulse and its reference polarity signal. A redundancy is provided to a reference detection polarity signal so that a read signal can be detected even if any one of the read signals of the sector marks is dropped out.
    Type: Application
    Filed: April 24, 1998
    Publication date: August 16, 2001
    Applicant: FUJITSU LIMITED
    Inventors: MASARU SAIKI, TSUTOMU SASAKI, HIROKAZU ISHIZAKI, EIJI OKAMURA, TATSUYA GOFUKU, NORIHIKO SUZUKI, KOICHI TOHKAIRIN, HIROFUMI SUZUKI, KENJI ENDO, CHIHIRO ONO, KAZUHIDE OHBA, ATSUSHI SATOH, EISAKU TAKAHASHI, TAKASHI TOKAIRIN, ISAO SUDA, TAKAHIRO ONO
  • Patent number: 6137646
    Abstract: A disk apparatus has a disk medium with sector areas that have a servo area and a data area along the same cylinder. The servo areas also have a sector mark indicative of the servo area, a code indicative of a cylinder address, and a predetermined servo pattern to detect a head position, all magnetically recorded in the servo area. A disk control section uses a head portion to detect the head position on the basis of a read signal of the servo pattern and positions the head portion at an arbitrary cylinder to perform reading and writing operations. The disk apparatus also has a time measuring counter for starting to measure an elapsed time each time a predetermined position in the servo area is detected, and a time setting register for storing a time from a detection time point of the predetermined position in the servo area to the generation of the sector pulse.
    Type: Grant
    Filed: June 10, 1997
    Date of Patent: October 24, 2000
    Assignee: Fujitsu Limited
    Inventors: Eiji Okamura, Tatsuya Gofuku, Chihiro Ono, Kazuhide Ohba, Atsushi Satoh, Eisaku Takahashi, Takashi Tokairin, Isao Suda
  • Patent number: 5798885
    Abstract: For a balance adjustment due to a reduction in size and weight of an actuator, an arm portion, an axis attaching portion, and a coil supporting portion are arranged so that the centers of gravity on the coil side are located on a straight line connecting a rotational center and the center of gravity on the head side. Further, the improvement of an assembling efficiency of a VCM, an increase in torque, a one-touch fixing of an FPC connecting band, a noise prevention of a read pattern, and an insulation between the base and cover due to a bias of an MR read head are accomplished. A sector mark is detected by comparing a peak detection pulse and its reference polarity signal. A redundancy is provided to a reference detection polarity signal so that a read signal can be detected even if any one of the read signals of the sector marks is dropped out.
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: August 25, 1998
    Assignee: Fujitsu Limited
    Inventors: Masaru Saiki, Tsutomu Sasaki, Hirokazu Ishizaki, Eiji Okamura, Tatsuya Gofuku, Norihiko Suzuki, Koichi Tohkairin, Hirofumi Suzuki, Kenji Endo, Chihiro Ono, Kazuhide Ohba, Atsushi Satoh, Eisaku Takahashi, Takashi Tokairin, Isao Suda, Takahiro Ono