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:
Jul. 29, 1997
Filed:
Aug. 09, 1995
Thomas Karte, Lemgo, DE;
Mannesmann Aktiengesellschaft, Dusseldorf, DE;
Abstract
A device for operating a servo drive having a positioning element controlled by a pressure medium. The device includes an electrical control unit generating a control signal based upon the position of the positioning element, a pre-control system connected to receive the control signal through an electrical control path and a main control system controlled by the pre-control system to operate the servo drive by moving the positioning element. A switching element is positioned between the electrical control unit and the pre-control system and opens the electrical control path prohibiting the transmission of the control signal upon detecting operation malfunction. Upon opening of the control path, the pre-control system acts to switch the main control system into a deventilation mode and said positioning element is moved into a predetermined 'fail safe' position deventilating the positioning volume of the drive.