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. 04, 2017
Filed:
Nov. 06, 2015
Zf Friedrichshafen Ag, Friedrichshafen, DE;
Sven Bieber, Bermatingen, DE;
Jan-Frederik Kuhn, Friedrichshafen, DE;
Marcus Hiemer, Meckenbeuren, DE;
Stephan Schinacher, Egesheim, DE;
Mario Brugger, Tettnang, DE;
Markus Lukassek, Friedrichshafen, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A method for determining a draining behavior of a hydraulically actuated transmission shifting element. By applying actuating pressure, the shifting element is changed from a completely drained, open operating condition to a completely filled closed operating condition, and the reference filling time, until the closed condition has been reached, is determined. Upon recognition of the closed condition, then by adjusting the actuating pressure for a predefined draining time, the shifting element is changed to its open condition and, thereafter, again completely filled and closed. Upon recognition of the closed condition, the shifting element is actuated direction toward the open condition by reducing the actuating pressure. Then, before completely opening, the shifting element is again returned to its closed operating condition and the filling time, until the partially drained shifting element has reached the completely filled and closed operating condition, is determined.