Patents by Inventor Sayuri Tsubata

Sayuri Tsubata 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).

  • Lubricating oil for fluid dynamic bearing and spindle motor equipped with the lubricating oil
    Patent number: 10280382
    Abstract: The invention provides a lubricating oil for fluid dynamic bearing including as a base oil a monoester oil free of unsaturated bond, and having an absolute viscosity of 2.0 to 3.0 mPa·s at 100° C. a viscosity index of 130 or more and a pour point of ?20° C. or less.
    Type: Grant
    Filed: April 28, 2016
    Date of Patent: May 7, 2019
    Assignees: KYODO YUSHI CO., LTD., NIDEC CORPORATION
    Inventors: Iwaki Hirooka, Takayuki Oe, Sayuri Tsubata, Yuji Hagiwara
  • LUBRICATING OIL FOR FLUID DYNAMIC BEARING AND SPINDLE MOTOR EQUIPPED WITH THE LUBRICATING OIL
    Publication number: 20160319215
    Abstract: The invention provides a lubricating oil for fluid dynamic bearing including as a base oil a monoester oil free of unsaturated bond, and having an absolute viscosity of 2.0 to 3.0 mPa·s at 100° C. a viscosity index of 130 or more and a pour point of ?20° C. or less.
    Type: Application
    Filed: April 28, 2016
    Publication date: November 3, 2016
    Inventors: Iwaki HIROOKA, Takayuki OE, Sayuri TSUBATA, Yuji HAGIWARA
  • METHOD OF PREVENTING LUBRICANT FROM DETERIORATING, LUBRICANT, AND DYNAMIC-PRESSURE BEARING DEVICE
    Publication number: 20090247433
    Abstract: Disclosed are a lubricant whose oxidation degradation is inhibited, and a dynamic pressure bearing device which has a long lifespan by prolonging the period of time of depression of a lubricating function of the lubricant occurring as a result of oxidation degradation. Ester-based lubricating oil serving as the lubricant is brought into continuous or intermittent contact with an ionic compound or an ionic compound solution obtained by dissolving the ionic compound in a solvent. In the dynamic pressure bearing device, the ionic compound is provided in a portion of a bearing or a shaft member and is thus brought into contact with the lubricating oil, in which the ionic compound or ionic compound solution is substantially insoluble in the ester-based lubricating oil.
    Type: Application
    Filed: June 15, 2007
    Publication date: October 1, 2009
    Applicant: NIDEC CORPORATION
    Inventors: Sayuri Tsubata, Chikara Sagae, Toshimasa Kobayashi