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:
Mar. 29, 1994
Filed:
Oct. 09, 1990
Nippon Seiko Kabushiki Kaisha, Tokyo, JP;
Abstract
A long-life bearing steel and a long-life rolling bearing made of the steel are disclosed. In the steel, the number of oxide or oxide-based inclusion particles in a given unit area A of 160 mm.sup.3 with an average particle size of 3 to 30 .mu.m is 80 or less and an abundance of oxide or oxide-base inclusion particles with 10 .mu.m or more average particle size to oxide or oxide-based inclusion particles having an average particle size of 3 to 30 .mu.m is below 2%. An electron beam melting extraction evaluation method irradiating electron beam under the following condition guarantees the cleanness of the steel: 350 V+100.ltoreq.J.ltoreq.700 V+200, wherein J represents electric charge power in W provided by electron beam and V represents a sample volume in cm.sup.3.