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:
Oct. 18, 1983
Filed:
Dec. 10, 1981
Richard W Dymond, Rochester, MI (US);
TRW Inc., Cleveland, OH (US);
Abstract
An improved power steering apparatus includes a pressure modulation assembly which modulates the fluid pressure transmitted from a power steering control valve to a power steering motor. The modulation assembly varies the fluid pressure output from the steering control valve as a direct function of vehicle speed. This results in relatively easy steering for parking and low speed maneuvers and a firmer feel for maneuvers at higher speeds. The pressure modulation assembly is connected in series fluid communication with and between the power steering control valve and the power steering motor and includes a pair of pressure modulation valves. Fluid for actuating the power steering motor flows from the power steering control valve through the pressure modulation valves to the power steering motor. The pressure modulation valves are biased closed by the output pressure from an auxiliary pump which is driven at a speed which varies as a function of vehicle speed. Thus, the pressure of the fluid delivered to the power steering motor is reduced by the pressure modulation valve to an extent determined by the magnitude of the biasing force derived from the speed dependent auxiliary pump.