Patents by Inventor Mario Yamaguchi

Mario Yamaguchi 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: 6757120
    Abstract: A dynamic method and apparatus are provided for controlling head fly characteristics in a disk drive. A plurality of charge surfaces is provided with a transducer head slider assembly. At least one head fly characteristic is monitored during operation of the disk drive. An identified current head fly characteristic is compared with a predefined head fly characteristic to identify a difference value. A charge and potential of the plurality of charge surfaces are dynamically controlled responsive to the identified difference value. Dynamically controlling the charge and potential of the plurality of charge surfaces enables both dynamically controlling flyheight of the transducer head slider assembly and dynamically controlling angles of the transducer head slider assembly relative to an associated disk surface.
    Type: Grant
    Filed: March 7, 2002
    Date of Patent: June 29, 2004
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Yoichi Minoshima, Mario Yamaguchi
  • Publication number: 20030169526
    Abstract: A dynamic method and apparatus are provided for controlling head fly characteristics in a disk drive. A plurality of charge surfaces is provided with a transducer head slider assembly. At least one head fly characteristic is monitored during operation of the disk drive. An identified current head fly characteristic is compared with a predefined head fly characteristic to identify a difference value. A charge and potential of the plurality of charge surfaces are dynamically controlled responsive to the identified difference value. Dynamically controlling the charge and potential of the plurality of charge surfaces enables both dynamically controlling flyheight of the transducer head slider assembly and dynamically controlling angles of the transducer head slider assembly relative to an associated disk surface.
    Type: Application
    Filed: March 7, 2002
    Publication date: September 11, 2003
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yoichi Minoshima, Mario Yamaguchi
  • Patent number: 5864440
    Abstract: When writing user data D, the user data D is stored in a register 46, and using both the user data D and the sector information (ID) of the user data D, an error correction code ECC is generated by an ECC generation algorithm Ar. A stored information Rw made up of the user data D and the generated ECC is written on a disk. In the reading, the user data Dr of a read record Rr is temporarily stored in the register 46, and an ECC check algorithm is executed. This ECC check is executed for combined data of the user data Dr and its position information. When any error is found in the position information portion in the combined data, the user data is determined that the read user data is wrongly addressed. When an error is found in the user data Dr portion, the user data is corrected by ECC and the corrected user data is output.
    Type: Grant
    Filed: December 6, 1995
    Date of Patent: January 26, 1999
    Assignee: International Business Machines Corporation
    Inventors: Minoru Hashimoto, Jon Haswell, Tatsuya Sakai, Mario Yamaguchi
  • Patent number: 5765189
    Abstract: A system manages data transfer between a computer, a data storage disk, and a data buffer which is associated with the disk. Upon receipt of a write request during data read-ahead from the disk to the buffer, the system preempts the read-ahead to write the data to the disk only when the target write track on the disk is different from the track being read ahead into the buffer. Otherwise, the system permits read-ahead to continue until the target write sector is positioned beneath the disk drive head. Also, upon receipt of a read request during cache writing from the buffer to the disk, the system immediately satisfies the read request prior to completing the cache writing when the requested read data is contained in the buffer. Moreover, the system provides for dynamic switching between a data read-ahead preempt policy and a data read-ahead no-preempt policy based upon parallel monitoring and comparison of data request service times under both policies.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: June 9, 1998
    Assignee: International Business Machines Corporation
    Inventors: Richard Kent Treiber, Jonathan Mark Haswell, Spencer Wah-Fung Ng, Mario Yamaguchi
  • Patent number: 5566317
    Abstract: A system manages data transfer between a computer, a data storage disk, and a data buffer which is associated with the disk. Upon receipt of a write request during data read-ahead from the disk to the buffer, the system preempts the read-ahead to write the data to the disk only when the target write track on the disk is different from the track being read ahead into the buffer. Otherwise, the system permits read-ahead to continue until the target write sector is positioned beneath the disk drive head. Also, upon receipt of a read request during cache writing from the buffer to the disk, the system immediately satisfies the read request prior to completing the cache writing when the requested read data is contained in the buffer. Moreover, the system provides for dynamic switching between a data read-ahead preempt policy and a data read-ahead no-preempt policy based upon parallel monitoring and comparison of data request service times under both policies.
    Type: Grant
    Filed: June 14, 1994
    Date of Patent: October 15, 1996
    Assignee: International Business Machines Corporation
    Inventors: Richard K. Treiber, Jonathan M. Haswell, Spencer W. Ng, Mario Yamaguchi