Patents by Inventor Eiji Hirakawa

Eiji Hirakawa 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: 7381363
    Abstract: A plasma processing apparatus for powder, and a plasma processing method of powder, in which a powder supply nozzle is provided to supply a powder material into plasma flame generated inside a high-frequency coil, the powder supply nozzle arranged substantially radially centrally of the high-frequency coil comprises a revolving flow forming device, for example, a spiral-shaped plate, to cause a carrier gas and the powder material to form therein a revolving flow with an axis thereof directed axially of the high-frequency coil, and the revolving flow is discharged from an outlet at an end of the nozzle. More preferably, a transition space is provided between the outlet at the end of the nozzle and the revolving flow forming device, and the outlet at the end of the nozzle is made small in diameter.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: June 3, 2008
    Assignee: Hitachi Metals, Ltd.
    Inventors: Shujiroh Uesaka, Gang Han, Eiji Hirakawa
  • Patent number: 7135141
    Abstract: A method of manufacturing a sintered body, in which a material powder composed of metallic powder or alloy powder, a getter material having a higher oxidation potential than that of the material powder, and a hydride, which constitutes a hydrogen source, are sealed under reduced pressure in a metallic container, and subjected to pressurized sintering while being heated. The pressurized sintering is performed by keeping the metallic container at pressure not higher than 50 MPa and at temperature not lower than 500° C. for 1 to 50 hours, and then sintering the metallic powder and the alloy powder at pressure higher than 50 MPa and at temperature not higher than 1340° C.
    Type: Grant
    Filed: March 29, 2004
    Date of Patent: November 14, 2006
    Assignee: Hitachi Metals, Ltd.
    Inventors: Gang Han, Tomonori Ueno, Eiji Hirakawa, Shujiro Uesaka
  • Publication number: 20050183542
    Abstract: A plasma processing apparatus for powder, and a plasma processing method of powder, in which a powder supply nozzle is provided to supply a powder material into plasma flame generated inside a high-frequency coil, the powder supply nozzle arranged substantially radially centrally of the high-frequency coil comprises a revolving flow forming device, for example, a spiral-shaped plate, to cause a carrier gas and the powder material to form therein a revolving flow with an axis thereof directed axially of the high-frequency coil, and the revolving flow is discharged from an outlet at an end of the nozzle. More preferably, a transition space is provided between the outlet at the end of the nozzle and the revolving flow forming device, and the outlet at the end of the nozzle is made small in diameter.
    Type: Application
    Filed: November 29, 2004
    Publication date: August 25, 2005
    Inventors: Shujiroh Uesaka, Gang Han, Eiji Hirakawa
  • Publication number: 20040191108
    Abstract: A method of manufacturing a sintered body, in which a material powder composed of metallic powder or alloy powder, a getter material having a higher oxidation potential than that of the material powder, and a hydride, which constitutes a hydrogen source, are sealed under reduced pressure in a metallic container, and subjected to pressurized sintering while being heated. The pressurized sintering is performed by keeping the metallic container at pressure not higher than 50 MPa and at temperature not lower than 500° C. for 1 to 50 hours, and then sintering the metallic powder and the alloy powder at pressure higher than 50 MPa and at temperature not higher than 1340° C.
    Type: Application
    Filed: March 29, 2004
    Publication date: September 30, 2004
    Applicant: HITACHI METALS, LTD.
    Inventors: Gang Han, Tomonori Ueno, Eiji Hirakawa, Shujiro Uesaka
  • Patent number: 6110598
    Abstract: A method for forming a lamination structure of a tantalum nitride film and a tantalum thin film free of nitrogen overlying the tantalum nitride film, which have reduced resistivities, wherein a gas pressure during sputtering for growing the tantalum nitride film is limited to a predetermined value not more than about 0.5 pa so that the tantalum nitride film has a hexagonal crystal structure and the tantalum thin film free of nitrogen has a BCC structure with lattice spacing close to that of the tantalum nitride film hexagonal crystal structure.
    Type: Grant
    Filed: October 26, 1998
    Date of Patent: August 29, 2000
    Assignees: NEC Corporation, Hitachi Metals, Ltd.
    Inventors: Akitoshi Maeda, Hideo Murata, Eiji Hirakawa
  • Patent number: 5919321
    Abstract: A novel metal silicide target material is provided which can effectively restrict the occurrence of fine particles. The target material has a structure comprising metal silicide and free silicon, which material has a relative density more than 100% which relative density is defined by a ratio of a true density of the target material to a theoretical density obtained by calculation, and free silicon portions in the structure of the target material which free silicon portions are provided with Vickers hardness less than 1,100 or which free silicon portions are provided with dislocation-undetectable areas each having a diameter not less than 1 .mu.m. Further, it is desirable that a rupture load evaluated by acoustic emission at which rupture load there occurs rupture in a scratching test of the surface of target material by acoustic emission is not less than 50N.
    Type: Grant
    Filed: June 10, 1997
    Date of Patent: July 6, 1999
    Assignee: Hitachi Metals, Ltd.
    Inventor: Eiji Hirakawa