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:
Nov. 04, 1986
Filed:
Jun. 14, 1982
James K Yip, Richfield, MN (US);
William J Novacek, Bloomington, MN (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
An improved fluid controller (17) is disclosed of the type for use in a load sensing hydrostatic steering system. The system includes a load sensing priority flow control valve (15) of the type which operates on a dynamic load signal. The controller includes a spool valve (95) and a sleeve valve (97) which cooperate to define a plurality of orifices including a main variable flow control orifice (71) and a variable orifice (75) through which fluid flows from the return side of a steering cylinder (19) to the return port (25) of the controller. A variable drain orifice (76) communicates between the main flow path, downstream of the main orifice (71) and the return port (25). As the controller valving moves from its neutral position toward an operating position, the orifice (75) begins to open at least as soon as the main orifice (71) and reaches a predetermined flow area before the main orifice (71) reaches that predetermined flow area. In addition, the drain orifice (76) remains open at least until the variable orifice (75) begins to open to reduce undesirable high transition pressures in the controller.