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:
Mar. 21, 1989
Filed:
Jun. 09, 1987
James A Miller, Cedar Falls, IA (US);
Deere & Company, Moline, IL (US);
Abstract
A gain reduction circuit is provided for use with a pressure flow compensated variable displacement pump in a power-on-demand hydraulic system. An orifice and a check valve are connected in parallel between a pressure-flow compensating valve and the control for the variable displacement pump. A second orifice is connected between the pump control and sump. A relief valve is connected in parallel with both orifices. The circuit operates to allow a quick increase in pump output, while damping variations in the pump control to prevent or minimize oscillation of the pump outlet pressure around the desired value. In alternative embodiments, the check valve may be omitted if larger orifices are used, or the check valve may be provided and the second orifice omitted.