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. 05, 1999
Filed:
Feb. 23, 1998
David W Thomas, Plymouth, MN (US);
David E Ewel, Eden Prairie, MN (US);
Timothy A Hjelsand, Waconia, MN (US);
Jerry F Carlin, Mound, MN (US);
Russell P Schuchmann, Milwaukee, WI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A hydrostatic power steering system comprising a fluid motor (19) which receives pressurized fluid from a controller (17) in response to the rotation of a vehicle steering wheel (W). As the motor (19) or the steered wheels reach the stops, control logic (31) receives signals (37,77) representing steered wheel and steering wheel position, respectively, and generates appropriate command signals (33,27) to a pressure reducing/relieving valve (15) and to a proportional electromagnetic valve (23), respectively, closing the valve (15) somewhat, and opening the valve (23). A pressure differential is built between an additional fluid path (21) and the high pressure conduit (15c) between the controller (17) and the fluid motor (19). Pressure is communicated through the valve (23) into the conduit (51c), and back into the fluid meter (43) of the controller, preventing any further rotation thereof in response to an attempt to turn the steering wheel, thus eliminating travel limit slip.