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:
May. 29, 2012
Filed:
Jun. 29, 2007
Rainer Petzold, Friedrichshafen, DE;
Martin Miller, Immenstaad, DE;
Mario Steinborn, Friedrichshafen, DE;
Peter Herter, Ravensburg, DE;
Franz Bitzer, Friedrichshafen, DE;
Rainer Petzold, Friedrichshafen, DE;
Martin Miller, Immenstaad, DE;
Mario Steinborn, Friedrichshafen, DE;
Peter Herter, Ravensburg, DE;
Franz Bitzer, Friedrichshafen, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A clutch system for producing and interrupting a force flow between the engine and transmission of a motor vehicle, with a clutch, which is disengaged unless actuated, and one or more valves, which regulate the flow of pressure medium and which are electrically actuated by a control and regulation unit. If there is electrical failure while driving and when a gear is engaged or when the vehicle is stationary, the engine is running and a transmission gear is engaged, unintended clutch engagement is prevented. The valves are designed such that if there is a failure of the voltage supply and consequently also of the actuation of the valves by the electronic control and regulation system, the operating condition of the clutch existing at the time of failure, namely the disengaged or engaged operating condition, remains as it is.