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:
Jun. 01, 2004
Filed:
Sep. 26, 2002
Tsutomu Ohkubo, Gunma, JP;
Takeshi Nakazawa, Gunma, JP;
NSK Ltd., Tokyo, JP;
Abstract
Between two mutually adjoining load balls , there is interposed a retaining piece having two concave surfaces which are respectively opposed to the two adjoining load balls . The retaining piece has an outside diameter dimension equal to or more than 0.5 times the outside diameter dimension of the load ball . Further, the retaining piece has an outside diameter dimension which, when the retaining piece passes through a screw groove circulation passage and a tube circulation passage, prevents the retaining piece from touching the inner walls of these screw groove circulation passage and tube circulation passage, or has an outside diameter dimension which is equal to or less than 0.9 times the outside diameter dimension of the load ball. Accordingly, it is possible to provide a ball screw mechanism which can prevent a retaining piece from interfering with the inner walls of circulation passages to circulate load balls stably to thereby prevent variations in torque as well as prevent the wear of the retaining piece to thereby enhance the durability thereof.