Patents by Inventor Shun-ichi Marumi

Shun-ichi Marumi 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).

  • Read-write head
    Patent number: 6275360
    Abstract: A read-write head is capable of suppressing fluctuation on a reproduced waveform caused by repetition of a writing and reading operation, and is capable suppressing noise appearing in the reproduced waveform just after a writing operation is carried out. The read-write head has an upper magnetic core, an upper shield also serving as an lower magnetic core, a lower shield and a magnetoresistive film arranged between the upper shield and the lower shield. The upper shield has a soft magnetic film having a magnitude of anisotropy field of 5 to 30 Oe, or is a multilayer film composed of a high saturation magnetic flux density film and a negative magneto-striction film. The lower shield has a soft magnetic film having a magnitude of anisotropy field of 5 to 30 Oe.
    Type: Grant
    Filed: September 24, 1998
    Date of Patent: August 14, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiro Nakamoto, Takashi Kawabe, Tetsuo Kobayashi, Shun-ichi Marumi, Shinji Narishige, Takao Imagawa