Patents by Inventor Hidenobu Mikami

Hidenobu Mikami 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).

  • Publication number: 20040033911
    Abstract: Disclosed is a grease composition comprising a base oil, a thickener, and an additive; the base oil having a kinetic viscosity of 20 to 150 mm2/s at 40° C., and the additive containing as an essential component 0.
    Type: Application
    Filed: July 21, 2003
    Publication date: February 19, 2004
    Inventors: Hidenobu Mikami, Takayuki Kawamura, Mitsunari Asao, Eiichirou Shimazu
  • Patent number: 6673750
    Abstract: Disclosed is a lubricating composition such as a lubricant, a lubricating grease, or a rust preventive oil for use in a torque limiter and a ball-and-roller bearing; the lubricating composition having chemical attack resistance for a synthetic resin molded product. The lubricating composition comprises as a base oil at least one synthetic saturated hydrocarbon oil selected from the group consisting of a poly-&agr;-olefin, and an ethylene-&agr;-olefin copolymer. When a phosphoric acid ester is used as a compounding agent, or at lease one lubricating grease selected from the group consisting of an urea compound, silica powder, and bentonite powder is mixed therein, the lubricating composition is a rust preventive oil using a metal salt of sulfonic acid and the like. The lubricating composition is suitably used for machine parts of a business machine including the synthetic resin molded product.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: January 6, 2004
    Assignee: NTN Corporation
    Inventors: Masakazu Hirata, Atsushi Morooka, Hidenobu Mikami, Toshiyuki Mizutani, Seiichi Takada, Masaaki Honda, Yoshihiko Oeda, Katsumi Nagano
  • Publication number: 20030153472
    Abstract: There is provided a durable low-torque lubricating oil for bearings and fluid dynamic bearings, porous oil-impregnated bearings and hydrodynamic type porous oil-impregnated bearings suitable for use as bearings in small-sized spindle motors for information equipment. The lubricating oil composition comprising (A) a diester of a monovalent aliphatic alcohol containing 6-10 carbon atoms and a saturated aliphatic dicarboxylic acid containing 10 carbon atoms as base oil and (B) 3-20% by weight of a low-viscosity lubricating oil with a kinematic viscosity of less than 11 mm2/s at 40 ° C., a fluid dynamic pressure bearing unit or a porous oil-impregnated bearing unit containing said lubricating oil composition or a spindle motor provided with said bearing unit.
    Type: Application
    Filed: December 23, 2002
    Publication date: August 14, 2003
    Inventors: Katsumi Nagano, Yoshihiko Oeda, Hidenobu Mikami, Tetsuya Kurimura
  • Patent number: 6605574
    Abstract: Disclosed is a grease sealed bearing for automobile that has the high temperature resistance as well as shear stability, and prevents the noise at low temperature as well as the brittle flaking under high speed rotation and high load. The grease comprises a base oil containing a synthesized hydrocarbon oil and one or more ester oils at a weight ratio of 0.1 to 0.49:0.9 to 0.51; 5 to 30% by weight of a urea based thickener, and 0.1 to 10% by weight of dithiozinc phosphate based on the whole grease. The grease sealed bearing for automobile is obtained by sealing a bearing used in a device driven by an automobile engine with the grease.
    Type: Grant
    Filed: January 16, 2002
    Date of Patent: August 12, 2003
    Assignee: NTN Corporation
    Inventors: Mitsunari Asao, Hidenobu Mikami, Takayuki Kawamura, Takahiro Koremoto, Kunio Takemura
  • Publication number: 20030069147
    Abstract: Disclosed is a grease that provides a prolonged lubricating lifetime to applied portions for use at high temperature, and a grease sealed bearing in which the bearing is sealed with this grease. This grease comprises a base oil, a thickener, and an amide-based wax. The amide-based wax is contained in an amount of 0.5 to 10% by weight based on the total amount of the grease, has a melting point of 80° C. or more, and an antioxidative ability to the base oil. The base oil is at least one base oil selected from the group consisting of an ether-based oil, an ester-based oil and a synthetic hydrocarbon oil, and has kinematic viscosity of 20 to 150 mm2/s at 40° C. The thickener is an urea-based thickener, and is contained in an amount of 5 to 30% by weight based on the total amount of the grease.
    Type: Application
    Filed: September 23, 2002
    Publication date: April 10, 2003
    Inventors: Takayuki Kawamura, Hidenobu Mikami, Mitsunari Asao, Yuji Oonuki, Toshiaki Endo
  • Publication number: 20030060376
    Abstract: Disclosed is a lubricating composition such as a lubricant, a lubricating grease, or a rust preventive oil for use in a torque limiter and a ball-and-roller bearing; the lubricating composition having chemical attack resistance for a synthetic resin molded product. The lubricating composition comprises as a base oil at least one synthetic saturated hydrocarbon oil selected from the group consisting of a poly-&agr;-olefin, and an ethylene-&agr;-olefin copolymer. When a phosphoric acid ester is used as a compounding agent, or at lease one lubricating grease selected from the group consisting of an urea compound, silica powder, and bentonite powder is mixed therein, the lubricating composition is a rust preventive oil using a metal salt of sulfonic acid and the like. The lubricating composition is suitably used for machine parts of a business machine including the synthetic resin molded product.
    Type: Application
    Filed: February 19, 2002
    Publication date: March 27, 2003
    Inventors: Masakazu Hirata, Atsushi Morooka, Hidenobu Mikami, Toshiyuki Mizutani, Seiichi Takada, Masaaki Honda, Yoshihiko Oeda, Katsumi Nagano
  • Publication number: 20030027731
    Abstract: A heat-resistant, high-speed, high-load rolling bearing for automotive accessories and electric part is provided which develops no abnormal flaking and is sufficiently long in life and superior in durability. It is a heat-resistant, high-speed, high-load rolling bearing in which is sealed a grease composition which comprises a base oil which is a mixture alkyldiphenyl ether oil and aromatic ester oil at the ratio (in weight) of 50:50 to 80:20, a diurea compound expressed by the following formula as a thickening agent, and 0.1 to 5 wt % of a passivating agent.
    Type: Application
    Filed: June 28, 2002
    Publication date: February 6, 2003
    Inventors: Takayuki Kawamura, Hidenobu Mikami, Mitsunari Asao
  • Publication number: 20020137639
    Abstract: Disclosed is a grease sealed bearing for automobile that has the high temperature resistance as well as shear stability, and prevents the noise at low temperature as well as the brittle flaking under high speed rotation and high load. The grease comprises a base oil containing a synthesized hydrocarbon oil and one or more ester oils at a weight ratio of 0.1 to 0.49:0.9 to 0.51; 5 to 30% by weight of a urea based thickener, and 0.1 to 10% by weight of dithiozinc phosphate based on the whole grease. The grease sealed bearing for automobile is obtained by sealing a bearing used in a device driven by an automobile engine with the grease.
    Type: Application
    Filed: January 16, 2002
    Publication date: September 26, 2002
    Inventors: Mitsunari Asao, Hidenobu Mikami, Takayuki Kawamura, Takahiro Koremoto, Kunio Takemura
  • Publication number: 20020107150
    Abstract: There are provided a lubricant composition for use in a ball-and-roller bearing with a smaller diameter, and a ball-and-roller bearing with a smaller diameter.
    Type: Application
    Filed: November 30, 2001
    Publication date: August 8, 2002
    Inventors: Hidenobu Mikami, Toshiyuki Mizutani, Masakazu Hirata
  • Patent number: 6417143
    Abstract: Rolling bearings are proposed in which acoustic deterioration is suppressed which maintaining low dust, low torque and long life. Also, a grease for rolling bearings is proposed which is less likely to scatter under centrifugal force at high speed rotation, whereby preventing malfunction and noise of electronic information devices. A lubricating oil film of an ester-series oil having a dynamic viscosity at 40° C. of 35 mm2/s or over is formed on the friction surface of a rolling bearing. There is also provided a high-speed rolling bearing in which a lubricating grease having its worked penetration (JIS K2220) adjusted to 175-250 is retained therein. The grease is preferably prepared by adding a thickening agent containing 50 wt % or more of an aliphatic lithium salt 12-24 in carbon number to a base oil comprising 30 wt % or more of an ester oil having a dynamic viscosity at 40° C. of 10 mm2/s or over, and having its worked penetration (JIS K2220) adjusted to 175-250.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: July 9, 2002
    Assignee: NTN Corporation
    Inventors: Hidenobu Mikami, Koya Ohira, Yoshinobu Akamatsu, Masaki Egami, Takashi Yasunishi
  • Patent number: 5804536
    Abstract: A solid lubricant for bearings which is less likely to be washed away by water or liquid mud coming into bearings, and which can restrain the development of rust even in a harsh environment where high-concentration salt water comes into the bearings. A rust preventive in the form of a sulfonate or a fatty polyhydric alcohol partial ester is added to a composition made up of 5-97% by weight of a lubricating grease, 93-1% by weight of an ultra-high-molecular-weight polyolefin powder, and 1-50% by weight of oil exudation inhibitor, and mixed together. The mixture is then heated to a temperature higher than the gel point of the ultra-high-molecular-weight polyolefin and preferably lower than the dropping point of the lubricating grease and molded into the solid lubricant for bearings.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: September 8, 1998
    Assignee: NTN Corporation
    Inventors: Mitsunari Asao, Hidenobu Mikami
  • Patent number: 5789354
    Abstract: A lubricative composition which can retain lubricating oil or grease without degrading it, which is heat-resistant and mechanically strong, and can be used continuously for a much longer time than conventional ones without the possibility of shortage of lubricant supply. It includes a first component, which is a modified silicone oil having reactive organic groups, a second component, which is a curing agent having organic groups that react with the reactive organic groups, and a third component, which is a lubricating oil or grease. The third component is retained in a three-dimensionally reticulated structure of silicone formed by polymerizing the first and second components in the third component. The third component has no compatibility with either the first or second components.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: August 4, 1998
    Assignee: NTN Corporation
    Inventors: Hidenobu Mikami, Mitsunari Asao
  • Patent number: 5301923
    Abstract: A grease composition sealed in a rolling contact bearing contains a base oil in the form of a mixture of an alkyldiphenylether oil and a poly-.alpha.-olefin oil. The weight ratio of the former to the latter is between 20:80 and 80:20. 5-40% by weight of thickening agent which is at least one of an aromatic diurea compound and an aromatic urea-urethane compound is added to the base oil. Further, a passivation oxidizing agent and an organic sulfonate are added.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: April 12, 1994
    Assignee: NTN Corporation
    Inventors: Mitsunari Asao, Osamu Hirano, Hidenobu Mikami