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. 20, 2016
Filed:
Apr. 22, 2015
Jtekt Corporation, Osaka-shi, Osaka, JP;
Masashi Yamaguchi, Toyota, JP;
JTEKT CORPORATION, Osaka-shi, JP;
Abstract
A ball screw mechanism includes: a rack shaft, on the outer peripheral surface of which a spiral rack screw groove is formed; a cylindrical nut, on the inner peripheral surface of which a spiral nut groove that faces the rack screw groove is formed; and a plurality of balls disposed in a rolling passage that is a space surrounded by the rack screw groove and the nut groove. The nut is provided with: shift portions provided at both ends of the nut groove to shift the track of the nut groove in the axial direction of the rack shaft from the rack screw groove and to displace the nut groove to be deeper in the radial direction of the rack shaft as the track is shifted; a circulation passage that connects between the shift portions; and passage entrances that each connect between the shift portion and the circulation passage.