Patents by Inventor Yuhji Yokoe

Yuhji Yokoe 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).

  • Disk drive device and data rewrite method thereof
    Patent number: 8068299
    Abstract: Embodiments of the present invention help to reduce the occurrence of read hard errors in a hard disk drive (HDD). According to one embodiment, a HDD rewrites data on all data tracks of a block M when the number of write operations to the block consisting of continuous plural data tracks. The HDD further rewrites data on continuous plural data tracks and adjacent to the block. Since the number of write operations is counted every block, a memory area to register the number of write operations can be reduced.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: November 29, 2011
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Toshihiko Tsunokawa, Nobuhiro Kuwamura, Masutaka Harada, Yuhji Yokoe, Takao Matsui
  • Disk drive device and data rewrite method thereof
    Publication number: 20080239901
    Abstract: Embodiments of the present invention help to reduce the occurrence of read hard errors in a hard disk drive (HDD). According to one embodiment, a HDD rewrites data on all data tracks of a block M when the number of write operations to the block consisting of continuous plural data tracks. The HDD further rewrites data on continuous plural data tracks and adjacent to the block. Since the number of write operations is counted every block, a memory area to register the number of write operations can be reduced.
    Type: Application
    Filed: March 26, 2008
    Publication date: October 2, 2008
    Inventors: Toshihiko Tsunokawa, Nobuhiro Kuwamura, Masutaka Harada, Yuhji Yokoe, Takao Matsui
  • Method for registering a defect map within a hard disk drive
    Patent number: 6850379
    Abstract: A method for registering a defect map within a hard disk drive is disclosed. A hard disk drive includes a recording disk, a head assembly, and a controller. Multiple sectors are formed on the recording disk, and the head assembly includes a head for reading/writing data from/to the recording disk. The controller, which controls the head assembly to read/write data from/to the recording disk, includes a defect sector positional information holding device and a sector identification device. The defect sector positional information holding device holds positional information of a defect sector disabled to read/write data therefrom/thereto the recording disk. The positional information includes the number of the defect sectors continued in a circumferential direction and in a radial direction of the recording disk.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: February 1, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Haruo Andoh, Takashi Kuroda, Yuhji Yokoe, Toshiaki Satoh
  • Method for registering a defect map within a hard disk drive
    Publication number: 20020122266
    Abstract: A method for registering a defect map within a hard disk drive is disclosed. A hard disk drive includes a recording disk, a head assembly, and a controller. Multiple sectors are formed on the recording disk, and the head assembly includes a head for reading/writing data from/to the recording disk. The controller, which controls the head assembly to read/write data from/to the recording disk, includes a defect sector positional information holding device and a sector identification device. The defect sector positional information holding device holds positional information of a defect sector disabled to read/write data therefrom/thereto the recording disk. The positional information includes the number of the defect sectors continued in a circumferential direction and in a radial direction of the recording disk.
    Type: Application
    Filed: February 14, 2002
    Publication date: September 5, 2002
    Applicant: International Business Machines Corporation
    Inventors: Haruo Andoh, Takashi Kuroda, Yuhji Yokoe, Toshiaki Satoh