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:
Dec. 26, 2000
Filed:
Nov. 06, 1998
NSK Ltd., , JP;
Abstract
At least one of input/output disks, a power roller and a cam disk of a toroidal type continuously variable transmission is formed of a high-cleanness steel in which a size of a maximum inclusion is estimated by the following extremum statistical process. In step S1, a plane including a central line of the high-cleanness steel is cut out in a direction of rolling of the high-cleanness steel. In step S2, a portion d of the cut-out cross-section, which is defined by 40% of a diameter D in the vicinity of the central line, is used as a to-be-tested surface. In step S3, a test reference area S.sub.0 is set at an area not less than 300 mm.sup.2 within the to-be-tested surface, and a root of an area of the maximum inclusion is measured five times or more. In step S4, a maximum inclusion distribution straight line is obtained. In step S5, the root, that is, the size of the area of the maximum inclusion within an estimation area S is estimated.