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:
Aug. 07, 2012
Filed:
Oct. 30, 2009
Wilfrid Eberhard, Tettnang, DE;
Gerhard Hermann Martin, Tettnang, DE;
Wilfrid Eberhard, Tettnang, DE;
Gerhard Hermann Martin, Tettnang, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A method for operating a vehicle drive train comprising a drive unit, a transmission, and an all-wheel splitter having a clutch. The all-wheel splitter is positioned between the transmission and the output and splits a transmission output torque to vary the torque distribution to driven axles of the output. The split of the output torque to the driven axles is performed by a control unit in such a way that the transmission output torque, less a predetermined nominal torque set by the all-wheel drive strategy, is transferred to a first axle while the nominal torque is transferred to a second axle. When defined operating conditions are met, a clutch monitoring function is activated and the nominal torque is replaced by a torque definition of the clutch monitoring function so that the torque which is transferred by clutch to the second driven axle, is increased, then kept constant, and thereafter reduced.