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. 16, 2019
Filed:
Jul. 19, 2016
Zf Friedrichshafen Ag, Friedrichshafen, DE;
Dennis Wohlfahrt, Meersburg, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A method of operating an automatic transmission of a motor vehicle, in which a hydraulic pump associated with a hydraulic system for the supply of pressure is driven by a drive motor. When the motor vehicle starts, a hydrodynamic starting element forms a driving connection between the drive motor and the automatic transmission. Hydraulic shifting elements (B, B, B, C, C) are actuated for engaging gear steps. When the drive motor is started, a shifting element (B, B, B, C, C) of the automatic transmission is engaged, and, during the engagement process of the shifting element (B, B, B, C, C), a time of a rotational speed variation (n, n) of the automatic transmission is determined. With the help of the determined rotational speed variation (n, n), a time point is determined at which a pressure present in the hydraulic system reaches or exceeds a target pressure level.