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. 04, 2008
Filed:
Oct. 13, 2006
Gunther Petrzik, St. Georgen, DE;
Guenter Ruehle, Loechgau, DE;
Josef Neuner, Raubling, DE;
Getrag Getriebe- und Zahnradfabrik Hermann Hagenmeyer GmbH & Cie AG, Untergruppenbach, DE;
Bayerische Motoren Werke Aktiengesellschaft, München, DE;
Abstract
A method for controlling a hydraulic circuit for a twin-clutch transmission, wherein the hydraulic circuit comprises a first and a second clutch that can be hydraulically actuated, the pressures of said clutches being controlled with respective pressure control valves, and wherein a safety circuit substantially guarantees a safe state for the hydraulic circuit if a malfunction occurs. The safety circuit is configured such that if a partial malfunction affecting only one of the two clutches occurs, the affected clutch is disengaged and if a total malfunction affecting both clutches occurs, the clutch with the lower clutch pressure at the time of the total malfunction is disengaged and the other clutch with the higher clutch pressure at the time of the total malfunction remains engaged to maintain the transfer of torque via said clutch.