Minebea Company, Limited

Nippon Grease Co., Ltd.

Other

Ntn Corporation

Jtekt Corporation

Koyo Seiko Company, Ltd.

Seiji Okamura

Hiroki Iwamatsu

Motoharu Akiyama

Hiroshi Komiya

Yasuhiro Miyamoto

Hidenobu Mikami

Toshihiro Kawaguchi

Masayuki Kitamura

Teruo Yoshida

Hiroyoshi Yasui

Masashi Mitsuoka

Toshikazu Kouno

Toshitaro Oguchi

A rolling bearing, for use in household appliances, having a high degree of quietness, an excellent durability at high temperatures and rotational speeds, a low torque, and excellent fretting property; and a lubricant composition which can be sealed into the rolling bearing. The lubricant composition includes a base oil and a thickening agent. The base oil is a mixed oil having the following characteristics of (a) to (c): (a) The base oil consists essentially of a synthetic hydrocarbon oil and an ester oil; (b) A kinematic viscosity of the mixed oil at 40&#xb0; C. is 40 to 70 mm/second; (c) A mixing weight ratio between the ester oil of the mixed oil and the synthetic hydrocarbon oil thereof is 30:70 to 70:30. The thickening agent comprises a diurea compound shown by a formula (1): where Rand Rare a straight-chain alkyl groups having 9 to 22 carbon atoms respectively, and Ris an aromatic hydrocarbon group having 6 to 15 carbon atoms. The lubricant composition is sealed into the rolling bearing.

Lubricant composition and sealed bearing thereof

A grease composition for a pivot assembly bearing is provided and includes a thickener of 5 to 25% by mass and a base oil of 95 to 75% by mass with respect to the total mass of the thickener and the base oil. Two or more ureas selected from: urea A: a urea comprising diurea compounds having an aliphatic (ALA)/alicyclic (ACA) substituent; urea B: a urea comprising diurea compounds having an alicyclic (ACA)/aromatic (ARA) substituent; and urea C: a urea comprising diurea compounds having an aromatic (ARA)/aliphatic (ALA) substituent are used as the thickener. A poly &#x3b1;-olefin mixture having a kinematic viscosity at 40&#xb0; C. of 40 to 70 mm/s prepared by mixing poly &#x3b1;-olefin (PAO HV) having a kinematic viscosity at 40&#xb0; C. of 350 to 450 mm/s with poly &#x3b1;-olefin (PAO LV) having a kinematic viscosity at 40&#xb0; C. of 25 to 40 mm/s in a mass ratio of 15:85 to 30:70 is used as a base oil. A lead free additive may be used as an additive.

Grease composition for pivot assembly bearing and bearing for pivot assembly

Bismuth dithiocarbamate (BiDTC) is added to a urea grease containing a lubricating base oil having a poly-&#x3b1;-olefin synthetic oil or a diphenyl ether synthetic oil and a diurea thickening agent, or a fluorine grease containing a lubricating base oil having fluorinated synthetic oil and a polytetrafluoroethylene thickening agent. By taking such constitution as described above, a surface film is formed on a surface of a raceway of any one of inner and outer rings or a surface of a rolling element of a bearing. Therefore, the rolling bearing in which a grease composition having the constitution is packed can maintain an excellent lubricity for a long period of time even under severe conditions such as a high rotation, a high temperature and a heavy load. Further, the grease composition for the rolling bearing is low in harmfulness to a human body and gives little load to the environment.

Grease composition for rolling bearing and rolling bearing using the same

A grease composition for bearings of information devices comprising a carbonate base oil, a lithium soap, and at least one organomolybdenum compound selected from molybdenum dithiophosphates and molybdenum dithiocarbanates.

Grease composition for bearings of information devices

The present invention is directed to a grease for a rolling bearing containing poly-&agr;-olefin synthetic oil or diphenyl ether synthetic oil, a diurea thickening agent, and an organic antimony compound or an organic molybdenum compound. The present invention is also directed to a rolling bearing in which the grease for a rolling bearing is sealed. The organic antimony compound or the organic molybdenum compound reacts with a metal composing inner and outer bearing rings and a rolling element to form a compound film contributing to the reduction of the force in the tangential direction on a raceway surface of the bearing rings and a surface of the rolling element, thereby preventing an excessively large force in the tangential direction under high-speed rotation. This enables to lengthen the life of the rolling bearing used under particularly severe conditions such as high temperature, high-speed rotation and high road.

Grease for rolling bearing and grease-sealed rolling bearing

Bearing grease composition for motor

The present invention provides a grease composition comprising a lubricating oil and a thickener, characterized in that the thickener is a diurea compound prepared by reacting a diisocyanate compound with cyclohexylamine and monoalkylphenylamine wherein the alkyl portion has 8 to 16 carbon atoms.

Diurea type grease composition

Growing community of inventors

Osaka, Japan

Seiji Okamura