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. 11, 2003
Filed:
Jul. 27, 2001
Martin Oberhäusser, Aschaffenburg, DE;
Thomas Weickert, Karsbach-Hessdorf, DE;
Bosch Rexroth AG, Lohr/Main, DE;
Abstract
A control arrangement to supply-pressure medium to at least two hydraulic consumers having a variable-displacement pump controlled according to required flow and the setting of which can be changed by a, pump controller as a function of highest load pressure of the actuated hydraulic consumers; two adjustable meter-in variable restrictors, a first of which is arranged between a feed line, which leads from the variable-displacement pump, and a first hydraulic consumer, and the second of which is arranged between the feed line and a second hydraulic consumer; and two pressure compensators, a first of which is connected downstream of the first meter-in variable restrictor and the second of which is connected downstream of the second meter-in variable restrictor, and the control piston of which can be acted on in opening direction by the pressure downstream of the associated meter-in variable restrictor. To ensure in this type control arrangement that a brief excess quantity from the variable-displacement pump is not passed on to the hydraulic consumers, the control pistons of the pressure compensators can be acted on in closing direction by a control pressure which is present in a rear control space, is derived from the feed pressure prevailing in the feed line with aid of a valve device and changes with the feed pressure. There is also a pressure differential valve which, with small structure, allows a pressure at its outlet to follow, with a fixed pressure difference, a rising pressure at its inlet. Together with a restricted pressure relief of the outlet to the tank, this type pressure differential valve ensures in each case a fixed pressure difference between the outlet pressure and the inlet pressure. This valve is particularly suitable for use in the control arrangement.