The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 13, 2010
Filed:
Sep. 25, 2006
Seiji Okamura, Osaka, JP;
Motoharu Akiyama, Nagano, JP;
Hiroki Iwamatsu, Hyogo, JP;
Yasuhiro Miyamoto, Hyogo, JP;
Seiji Okamura, Osaka, JP;
Motoharu Akiyama, Nagano, JP;
Hiroki Iwamatsu, Hyogo, JP;
Yasuhiro Miyamoto, Hyogo, JP;
Minebea Co., Ltd., Nagano, JP;
Nippon Grease Co., Ltd., Kobe-shi, JP;
Abstract
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 α-olefin mixture having a kinematic viscosity at 40° C. of 40 to 70 mm/s prepared by mixing poly α-olefin (PAO HV) having a kinematic viscosity at 40° C. of 350 to 450 mm/s with poly α-olefin (PAO LV) having a kinematic viscosity at 40° 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.