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. 09, 1989
Filed:
Oct. 03, 1988
William J Novacek, Bloomington, MN (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A fluid controller (15) is disclosed for controlling the flow of fluid to fluid pressure operated devices such as a vehicle steering cylinder (17). The controller is of the type including a valve spool (35) and a valve sleeve (37) in which the various ports, passages and fluid paths are non-symmetrical. Metered, pressurized fluid is communicated through axial slots (85) in the valve spool and is communicated through cylinder ports (73) for a right turn condition, or through cylinder ports (75) for a left turn condition. The right turn cylinder ports (73) are located further axially than are the left turn cylinder ports (75) from the end of the spool and sleeve which communicate with the return port. As a result, metered, pressurized fluid has a longer leakage path for a right turn than for a left turn. In accordance with the invention, the timing of the variable return flow control orifice (A5-R) is advanced, relative to the timing of the variable return flow control orifice (A5-L) to compensate for the unequal leakage paths in the right and left turn conditions, thereby substantially eliminating steering wheel precession.