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:
Jul. 19, 1977
Filed:
Nov. 14, 1975
David A Galonska, Saginaw, MI (US);
James B McCarthy, Saginaw, MI (US);
Joseph A Rutkiewicz, Saginaw, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
This power steering gear comprises a piston nut movably mounted in a housing for turning a gear sector and the steerable wheels of a vehicle operatively connected thereto. The piston nut is mechanically moved by a rotatable screw, threadedly engaged with the piston nut and operatively connected to an input stub shaft. Hydraulic power assist is provided with the piston nut forming separate expansible and contractible chambers filled with hydraulic fluid and controlled by integral valve means in the gear. The threads of the piston nut and screw are profiled to contact at their minor diameters to increase thread efficiency by reducing the friction radius. The threads of the piston nut are made with optimized thickness to reduce flank clearance to further restrict the hydraulic flow path through the thread to effectively seal the chambers from each other.