Nippon Grease Co., Ltd.

Jtekt Corporation

Ntn Corporation

Masashi Mitsuoka

Hiroki Iwamatsu

Koji Yoshizaki

Hidenobu Mikami

Seiji Okamura

Kensuke Suzuki

Michiru Ueda

Komatsugu Nishimura

Kunihiro Yamaguchi

A grease composition which is excellent in seizure resistance can be provided without deteriorating resistance to stirring in the rolling device, and a rolling device in which the grease composition intervenes to a predetermined portion can be also provided by use of a grease composition comprising a base oil and a thickener, the thickener being a diurea compound obtained by allowing an amine mixture comprising alkylphenylamine, an alkyl group of which has 8 to 16 carbon atoms, and cyclohexylamine, to react with a diisocyanate compound, the amount of cyclohexylamine in the amine mixture being 80% by mole or more and less than 91% by mole, and a worked penetration being 300 to 330.

Grease composition and rolling device

There is provided a rolling bearing which inhibits spalling of a rolling element and has a long service life even under rigorous environments. The rolling bearing comprises grease for lubricating rolling contact parts and/or sliding contact parts between a first raceway surface and a rolling elements and/or between a second raceway surface and a rolling elements, wherein the grease comprises a base oil, a thickener and an extreme pressure additive, the thickener is a diurea compound obtained by allowing an amine mixture comprising alkylphenylamine, alkyl group of which has 8 to 16 carbon atoms, and cyclohexylamine, to react with a diisocyanate compound, an amount of cyclohexylamine in the total amount of the alkylphenylamine and cyclohexylamine is from 91 to 99% by mole, and a reaction temperature of the extreme pressure additive with iron is 260&#xb0; C. or lower.

Rolling bearing

There is provided a grease composition, in which a grease film on the surface of the applied part is made thicker compared with conventional grease compositions, this thickness is maintained for a long period of time, and as a result, a longer service life against seizure compared with conventional grease compositions is assured. The grease composition comprises a base oil and a thickener, wherein the thickener is a diurea compound obtained by allowing an amine mixture comprising alkylphenylamine, an alkyl group of which has 8 to 16 carbon atoms, and cyclohexylamine, to react with a diisocyanate compound, and an amount of cyclohexylamine in the total amount of the alkylphenylamine and cyclohexylamine is from 91 to 99% by mole.

Grease composition

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

Growing community of inventors

Kobe, Japan

Masashi Mitsuoka