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:
Sep. 29, 2009
Filed:
Dec. 20, 2004
Applicants:
Yasuyuki Watanabe, Iwata, JP;
Kousuke Obayashi, Iwata, JP;
Inventors:
Yasuyuki Watanabe, Iwata, JP;
Kousuke Obayashi, Iwata, JP;
Assignee:
NTN Corporation, Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16C 33/62 (2006.01);
U.S. Cl.
CPC ...
Abstract
A thrust needle roller bearing has a washer formed of a thin steel plate and needle rollers, at least said washer has a nitrogen enriched layer at a surface layer portion, amount of retained austenite in said surface layer portion is at least 5 volume % and at most 25 volume %, and austenite grain number of said surface layer portion is 11 or higher. Thus, a long life thrust needle roller bearing resistant to an early failure caused by surface damage such as surface-originated flaking and also resistant to common, load dependent rolling contact fatigue can be provided.