Patents by Inventor Tsunekazu Saigo

Tsunekazu Saigo 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: 7002071
    Abstract: A thermoelectric conversion material is formed of a polycrystal structure of crystal grains composed of a silicon-rich phase, and an added element-rich phase in which at least one type of added element is deposited at the grain boundary thereof, the result of which is an extremely large Seebeck coefficient and low thermal conductivity, allowing the thermoelectric conversion rate to be raised dramatically, and affording a silicon-based thermoelectric conversion material composed chiefly of silicon, which is an abundant resource, and which causes extremely low environmental pollution.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: February 21, 2006
    Assignee: Sumitomo Special Metals Co. Ltd.
    Inventors: Nobuhiro Sadatomi, Osamu Yamashita, Tsunekazu Saigo, Masao Noumi
  • Publication number: 20040031515
    Abstract: A high-performance thermoelectric conversion element using an Si-group thermoelectric conversion material, and an thermoelectric conversion element capable of providing a high-out-put power by improving a power generating efficiency, wherein the thermal expansion coefficient of an electrode material is set to up to 10 ppm/K in order to provide a good electrode joining between a p-type thermoelectric conversion material and a n-type thermoelectric conversion material consisting of an Si-group thermoelectric conversion material to thereby ease thermal stress and prevent cracking and breaking at a joining portion, and, in joining, a brazing filler material selected according to a working temperature range is interposed to thereby provide good joining characteristics, reduce an output loss, and improve a heat resistance and a heat-cycle resistance.
    Type: Application
    Filed: July 8, 2003
    Publication date: February 19, 2004
    Inventors: Nobuhiro Sadatomi, Tsunekazu Saigo
  • Patent number: 6525260
    Abstract: A silicon-based polycrystal powder, which contains no more than 30 at % Ge, C, Sn, or another such element that does not generate carriers as well as an added element that does generate carriers, and which has a crystal structure including crystal grains made up of at least 80 at % silicon, and a grain boundary phase where at least one type of said added element is precipitated at the boundary of said crystal grains, is mixed with a clathrate compound powder with low thermal conductivity and electrical resistivity, and this mixture is subjected to hot compression molding, the product of which has a composite structure in which the particles of the clathrate compound polycrystals are disposed around the particles of the silicon-based polycrystals.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: February 25, 2003
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Osamu Yamashita, Nobuhiro Sadatomi, Tsunekazu Saigo
  • Patent number: 6506321
    Abstract: A silicon based conductive material based on a semiconductor silicon and having an electric resistivity of 10−3(&OHgr;·m) or less at ambient temperature which has been unattainable heretofore, while facilitating production and handling. An electric resistivity of 10−6 (&OHgr;·m) or less, which is common for conductors can be realized by adding relatively large quantities of various kinds of elements to silicon. The conductive material can be provided in a semiconductor silicon substrate in a desired pattern by ion beam implantation and patterning. It can be employed not only in the form of a substrate, a rod or a wire, but also in the form of fine particles dispersed in a resin or glass to be employed in various applications requiring conduction, including a conductive sheet material.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: January 14, 2003
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Osamu Yamashita, Nobuhiro Sadatomi, Tsunekazu Saigo, Shunichi Haruyama
  • Patent number: 6444049
    Abstract: Manufacture by rolling silicon steel having a silicon content of 3 wt % or greater and by rolling thin sendust sheet is implemented by powder metallurgical fabrication using powder as the starting raw material, and the average crystal grain size of the sheet-form sintered body or quick-cooled steel sheet is made 300 pm or less, whereby intra-grain slip transformation occurs after slip transformation in the grain boundaries, wherefore cold rolling is rendered possible. In addition, a mixture powder wherein pure iron powder and Fe—Si powder are mixed together in a prescribed proportion is fabricated with a powder metallurgy technique, and an iron-rich phase is caused to remain in the sintered body, whereby cold rolling is possible using the plastic transformation of those crystal grains. Furthermore, when a minute amount of a non-magnetic metal element such as Ti, V, or Al, etc.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: September 3, 2002
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Osamu Yamashita, Ken Makita, Masao Noumi, Tsunekazu Saigo
  • Publication number: 20020088485
    Abstract: It is an object of the present invention to provide a thermoelectric conversion material, and a method for manufacturing this material, with which the thermal conductivity of a silicon-based thermoelectric conversion material can be greatly lowered without lowering the Seebeck coefficient or electrical conductivity of the material, which affords a marked increase in the thermoelectric figure of merit.
    Type: Application
    Filed: August 17, 2001
    Publication date: July 11, 2002
    Inventors: Osamu Yamashita, Nobuhiro Sadatomi, Tsunekazu Saigo
  • Patent number: 5662943
    Abstract: The purpose of this invention is to present fabrication methods and equipment for granulated powders whereby, the reaction between the R--Fe--B-type or R--Co-type rare earth containing alloy powders and the binder is controlled, the residual oxygen and carbon content of the sintered products after sintering is reduced, and whereby it is possible to obtain isotropic or anisotropic granulated powders having good powder flowability and lubrication properties when molding. After stirring a slurry of rare earth containing alloy powders formed by adding a binder consisting of water and at least one of either methyl cellulose, polyacryl amide or polyvinyl alcohol, and mixing, oriented liquid droplets are formed by applying a magnetic field to the slurry to orientate the said powder particles and spraying within the chamber of a spray dryer apparatus.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: September 2, 1997
    Assignee: Sumitomo Special Metals Company Limited
    Inventors: Osamu Yamashita, Tsunekazu Saigo, Seiichi Kohara, Hirokazu Kitayama, Hiroshi Hashikawa
  • Patent number: 5575830
    Abstract: The purpose of this invention is to present fabrication methods and equipment for granulated powders whereby, the reaction between the R-Fe-B-type or R-Co-type rare earth containing alloy powders and the binder is controlled, the residual oxygen and carbon content of the sintered products after sintering is reduced, and whereby it is possible to obtain isotropic or anisotropic granulated powders having good powder flowability and lubrication properties when molding. After stirring a slurry of rare earth containing alloy powders formed by adding a binder consisting of water and at least one of either methyl cellulose, polyacryl amide or polyvinyl alcohol, and mixing, oriented liquid droplets are formed by applying a magnetic field to the slurry to orientate the said powder particles and spraying within the chamber of a spray dryer apparatus.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: November 19, 1996
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Osamu Yamashita, Tsunekazu Saigo, Seiichi Kohara, Hirokazu Kitayama, Hiroshi Hashikawa
  • Patent number: 5427734
    Abstract: The object of the invention is to provide a manufacturing method of a complex shaped R--Fe--B type sintered anisotropic magnet improved the moldability of injection molding and preventing the reaction between R ingredients and binder and controlled the degradation of magnetic characteristics due to residual carbon and oxygen. Utilizing the R--Fe--B type alloy powder or the resin coated said alloy powder, and methylcellulose and/or agar and water, instead of the usual thermoplastic binder, it is mixed and injection molded. The molded body is dehydrated by the freeze vacuum dry method to control the reaction between R ingredients and of the R--Fe--B alloy powder and water; furthermore, by administering the de-binder treatment in the hydrogen atmosphere, and sintering it after the dehydrogen treatment, residual oxygen and carbon in the R--Fe--B sintered body is drastically reduced, improving the moldability during the injection molding to obtain a three dimensionally complex shape sintered magnet.
    Type: Grant
    Filed: June 24, 1993
    Date of Patent: June 27, 1995
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Osamu Yamashita, Masahiro Asano, Tsunekazu Saigo