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:
May. 04, 1999
Filed:
Aug. 14, 1997
Thomson Saginaw Ball Screw Company, L.L.C., Saginaw, MI (US);
Abstract
A differential ball screw and nut assembly has an axially and rotatably fixed nut with an internal helical groove having a first lead to cooperate with a tubular ball screw having an external helical groove with a corresponding lead to provide a first raceway for a train of balls. The tubular ball screw also has an internal helical groove of the same hand with a second reduced lead relative to the first lead. A second rotatably fixed, radially inner screw having an external helical groove with a lead corresponding to the second lead cooperates with the internal groove of the tubular screw to provide a second raceway. A second train of load bearing balls transmits load between the tubular screw and second screw to move the screws differentially an axial distance corresponding to the number of rotations of the tubular screw times the lead differential.