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:
Jan. 02, 2001
Filed:
Aug. 12, 1998
Reinhold Schniederjan, Neu-Ulm, DE;
Brueninghaus Hydromatik GmbH, Elchingen, DE;
Abstract
The invention relates to a hydraulic controller, in particular for the control of the rotating mechanism of an excavator. In a hydraulic drive circuit a drive hydraulic pump (,) and a drive hydraulic motor are provided, which are connected via working lines (,). The hydraulic controller includes an adjustment arrangement (,) for adjusting a setting piston (,) arranged between two setting pressure chambers (,) and acting upon the displacement volume of the drive hydraulic pump (,). Further, a pre-control arrangement (,) is provided which acts upon one of the setting pressure chambers (,) with a setting pressure, in dependence upon the pressure difference between two control lines (,). In accordance with the development according to the invention, the precontrol arrangement (,) is connected with a feed line (,) via a pressure regulation valve (,), whereby the precontrol arrangement (,), in a control position (,), connects one of the two setting pressure chambers (,) with the feed line (,) via the pressure regulation valve (,) and connects the respective other setting pressure chamber (,) with a pressure fluid tank (,). In a neutral position (,), both setting pressure chambers (,) are connected with the feed line (,) via the pressure regulation valve (,).