Patents by Inventor Yoshihito Tachi

Yoshihito Tachi 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: 6903645
    Abstract: This invention provides a surface mounting type planar magnetic device comprised of upper ferrite magnetic film, lower ferrite magnetic film and a planar coil interposed therebetween. For applying surface mount technology, an opening is formed in the upper ferrite magnetic film above a coil terminal portion and then, an external electrode conductive with the coil terminal portion through the opening is formed on the upper ferrite magnetic film. Further, this surface mounting type planar magnetic device is of a thin structure and can be mounted on the surface of a printed board. Its power loss is small, its inductance is large, its frequency characteristic is excellent, the disparity of the characteristic is small and its reliability is excellent.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: June 7, 2005
    Assignees: Kawatetsu Mining Co., Ltd., Kabushiki Kaisha Toshiba
    Inventors: Tetsuhiko Mizoguchi, Tetsuo Inoue, Shigeru Yatabe, Yasutaka Fukuda, Yoshihito Tachi
  • Patent number: 6831543
    Abstract: A surface mounting type planar magnetic device comprised of upper ferrite magnetic film, lower ferrite magnetic film and a planar coil interposed therebetween. For applying surface mount technology, an opening is formed in the upper ferrite magnetic film above a coil terminal portion and then, an external electrode conductive with the coil terminal portion through the opening is formed on the upper ferrite magnetic film. Further, this surface mounting type planar magnetic device is of a thin structure and can be mounted on the surface of a printed board. Its power loss is small, its inductance is large, its frequency characteristic is excellent, the disparity of the characteristic is small and its reliability is excellent.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: December 14, 2004
    Assignees: Kawatetsu Mining Co., Ltd., Kabushiki Kaisha Toshiba
    Inventors: Tetsuhiko Mizoguchi, Tetsuo Inoue, Shigeru Yatabe, Yasutaka Fukuda, Yoshihito Tachi
  • Publication number: 20040166370
    Abstract: This invention provides a surface mounting type planar magnetic device comprised of upper ferrite magnetic film, lower ferrite magnetic film and a planar coil interposed therebetween. For applying surface mount technology, an opening is formed in the upper ferrite magnetic film above a coil terminal portion and then, an external electrode conductive with the coil terminal portion through the opening is formed on the upper ferrite magnetic film. Further, this surface mounting type planar magnetic device is of a thin structure and can be mounted on the surface of a printed board. Its power loss is small, its inductance is large, its frequency characteristic is excellent, the disparity of the characteristic is small and its reliability is excellent.
    Type: Application
    Filed: March 4, 2004
    Publication date: August 26, 2004
    Applicants: Kawatetsu Mining Co., Ltd., Kabushiki Kaisha Toshiba
    Inventors: Tetsuhiko Mizoguchi, Tetsuo Inoue, Shigeru Yatabe, Yasutaka Fukuda, Yoshihito Tachi
  • Patent number: 6756238
    Abstract: A domain controlled piezoelectnc single crystal is disclosed which uses a lateral vibration mode for an electromechanical coupling factor k31 not less than 70% and a piezoelectric constant −d31 not less than 1200 pC/N, with an electromechanical coupling factor k33 in the longitudinal vibration mode not less than 80% and a piezoelectric constant d33 not less than 800 pC/N. Also, a piezoelectric single crystal is disclosed which uses a high-performance longitudinal vibration mode with k31 not more than 30%. A fabrication method applies a DC electric field of 400 V/mm to 1500 V/mm for a maximum of two hours in a temperature range of 20° C. to 200° C. as polarization conditions in the thickness direction of the piezoelectric single crystal. The method can include cooling, or heating and cooling between temperature boundaries of rhombohedral and tetragonal crystals or between tetragonal and cubic crystals or within a cubic crystal temperature range.
    Type: Grant
    Filed: September 19, 2002
    Date of Patent: June 29, 2004
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventors: Toshio Ogawa, Mitsuyoshi Matsushita, Yoshihito Tachi
  • Publication number: 20030178914
    Abstract: A domain controlled piezoelectric single crystal is disclosed which uses a lateral vibration mode for an electromechanical coupling factor k31 not less than 70% and a piezoelectric constant −d31 not less than 1200 pC/N, with an electromechanical coupling factor k33 in the longitudinal vibration mode not less than 80% and a piezoelectric constant d33 not less than 800 pC/N. Also, a piezoelectric single crystal is disclosed which uses a high-performance longitudinal vibration mode with k31 not more than 30%. A fabrication method applies a DC electric field of 400 V/mm to 1500 V/mm for a maximum of two hours in a temperature range of 20° C. to 200° C. as polarization conditions in the thickness direction of the piezoelectric single crystal. The method can include cooling, or heating and cooling between temperature boundaries of rhombohedral and tetragonal crystals or between tetragonal and cubic crystals or within a cubic crystal temperature range.
    Type: Application
    Filed: September 19, 2002
    Publication date: September 25, 2003
    Applicants: KAWATETSU MINING CO., LTD.
    Inventors: Toshio Ogawa, Mitsuyoshi Matsushita, Yoshihito Tachi
  • Patent number: 6383626
    Abstract: A magnetic ferrite paste is applied onto an Si substrate, and then sintered to form thereon a magnetic ferrite film having a mean composition that comprises from 40 to 50 mol % of Fe2O3, from 15 to 35 mol % of ZnO, from 0 to 20 mol % of CuO, and from 0 to 10 mol % of Bi2O3 with NiO and inevitable impurities as the balance. The magnetic ferrite film thus formed on an Si substrate is for magnetic devices, and it forms a region not containing CuO or having a CuO content of at most 5 mol % around its interface directly adjacent to the surface of the Si substrate. The adhesiveness of the magnetic ferrite film to the underlying Si substrate is high, and the reliability of the magnetic device having the magnetic film is therefore high.
    Type: Grant
    Filed: April 12, 2000
    Date of Patent: May 7, 2002
    Assignee: Kawatetsu Mining Co., Ltd.
    Inventors: Yasutaka Fukuda, Yoshihito Tachi
  • Publication number: 20010024739
    Abstract: This invention provides a surface mounting type planar magnetic device comprised of upper ferrite magnetic film, lower ferrite magnetic film and a planar coil interposed therebetween. For applying surface mount technology, an opening is formed in the upper ferrite magnetic film above a coil terminal portion and then, an external electrode conductive with the coil terminal portion through the opening is formed on the upper ferrite magnetic film. Further, this surface mounting type planar magnetic device is of a thin structure and can be mounted on the surface of a printed board. Its power loss is small, its inductance is large, its frequency characteristic is excellent, the disparity of the characteristic is small and its reliability is excellent.
    Type: Application
    Filed: February 23, 2001
    Publication date: September 27, 2001
    Applicant: KAWATETSU MINING CO., LTD.
    Inventors: Tetsuhiko Mizoguchi, Tetsuo Inoue, Shigeru Yatabe, Yasutaka Fukuda, Yoshihito Tachi