Patents by Inventor Daigo Nagumo

Daigo Nagumo 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: 8518864
    Abstract: A grease composition for constant-velocity joints which is inexpensive and which and which has an improved anti-flaking property without using materials which have environmental burdens, and a constant-velocity joint enclosing this grease are provided. A grease composition for constant-velocity joints comprising: (a) a base oil, (b) a diurea thickener, (c) a zinc dialkyldithiophosphate, (d) a sulfurized molybdenum dialkyldithiocarbamate, (e) a zinc dialkyldithiocarbamate, and (f) a sulfur-nitrogen extreme pressure additive is provided.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: August 27, 2013
    Assignees: Kyodo Yushi Co., Ltd., NTN Corporation
    Inventors: Daigo Nagumo, Yuji Onuki, Shinya Kondo, Shin Tomogami, Shinichi Takabe
  • Publication number: 20120195678
    Abstract: The invention provides a grease composition containing (a) a base oil, (b) a lithium soap based thickener, (c) at least one stearic acid metallic salt selected from the group consisting of Ca stearate, Mg stearate and Zn stearate, (d) molybdenum dialkyl dithiocarbamate sulfide, and (e) zinc dialkyl dithiocarbamate sulfide. The present invention also provides a constant velocity joint such as a Barfield constant velocity joint (BJ), double offset constant velocity joint (DOJ), tripod constant velocity joint (TJ) or the like, containing the above-mentioned grease composition therein. The grease composition of the invention is excellent in antiwear properties and suitable for the constant velocity joint.
    Type: Application
    Filed: October 5, 2010
    Publication date: August 2, 2012
    Applicants: NTN CORPORATION, KYODO YUSHI CO., LTD.
    Inventors: Mitsuhiro Kakizaki, Daigo Nagumo, Michitaka Yoshihara, Shinichi Takabe
  • Publication number: 20100173807
    Abstract: A grease composition for constant-velocity joints which is inexpensive and which and which has an improved anti-flaking property without using materials which have environmental burdens, and a constant-velocity joint enclosing this grease are provided. A grease composition for constant-velocity joints comprising: (a) a base oil, (b) a diurea thickener, (c) a zinc dialkyldithiophosphate, (d) a sulfurized molybdenum dialkyldithiocarbamate, (e) a zinc dialkyldithiocarbamate, and (f) a sulfur-nitrogen extreme pressure additive is provided.
    Type: Application
    Filed: May 30, 2008
    Publication date: July 8, 2010
    Inventors: Daigo Nagumo, Yuji Onuki, Shinya Kondo, Shin Tomogami, Shinichi Takabe
  • Publication number: 20100029521
    Abstract: A grease composition which contains a large amount of thickener, and may prevent a flaking effectively for a long period of time, and machine elements in which the grease composition is filled are provided. A grease composition comprising a thickener and a base oil, characterized in that the thickener contains a diurea compound represented by the Formula (I): R1—NHCONH—R2—NHCONH—R3,??(I) wherein R1 and R3 are a phenyl group and/or a cyclohexyl group, R2 is a C6-C15 divalent hydrocarbon group, and the molar ratio of cyclohexyl group/(cyclohexyl group+phenyl group) in R1 and R3 is 0.95 to 0.10.
    Type: Application
    Filed: March 10, 2008
    Publication date: February 4, 2010
    Inventors: Shinya Kondo, Daigo Nagumo