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. 11, 1997
Filed:
Mar. 10, 1995
Applicant:
Inventors:
Assignee:
NSK, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B62D / ;
U.S. Cl.
CPC ...
180444 ; 74 8915 ; 384491 ; 384521 ; 384604 ;
Abstract
An electrically-operated power steering apparatus comprises a steering shaft, a rack shaft capable of linear movement for turning a steering running wheel a, rack-pinion gear for coupling the steering shaft with the rack shaft, and a ball screw mechanism including a screw groove formed on the rack shaft, a rotary ball screw nut fitted on the rack shaft, and plural balls positioned in a rolling path. The plural balls are comprised of bulbs of a larger diameter and balls of a smaller diameter, which are alternately arranged, and the smaller diameter is within a defined range.