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:
Nov. 26, 2002
Filed:
Oct. 04, 2001
Applicant:
Inventors:
Hiroshi Tako, Shizuoka-ken, JP;
Mamoru Mizutani, Osaka-fu, JP;
Assignee:
NTN Corporation, Osaka, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C23C 8/26 ;
U.S. Cl.
CPC ...
C23C 8/26 ;
Abstract
A bearing for use in the main spindle of a machine tool is provide, in which at least the raceway of the bearing contains by mass, C: 0.6-1.3%, Si: 0.3—3.0%, Mn: 0.2-.5%, P: 0.03% or less, S: 0.03% or less, Cr: 0.3-5.0%, Ni: 0.1-3.0%, Al: 0.050% or less, Ti: 0.003% or less, O: 0.0015% or less, N: 0.015% or less; and the rest is composed of Fe and unavoidable impurities. The raceway is tempered after either quenching or carbonitriding and its surface hardness presents at least HRC 58 after tempering.