Zf Friedrichshafen Ag

Reiner Kneer

Roland Mair

Thomas Jäger

Matthias Winkel

A method of controlling an automatic transmission of a vehicle in which a hold gear function is activated by a driver request and deactivated depending on a return condition. The method comprises the step of (a) determining the return condition by a change in operating state, and (b) deactivating the hold gear function if a temporary operating state, for which the hold function is requested, ends and a change takes place between one of uphill driving and downhill driving and between driving one of up and down a hill and driving on a same plane.

Method for controlling an automatic transmission of a motor vehicle

A method of controlling an automatic transmission of a vehicle in which a hold gear function is activated by a driver request and is deactivated depending on a return condition. To allow an effective, safe to operate, and comfortable use, the return condition depends on one of the following criteria or a useful combination of the same: a flexible time span, consideration of the vehicle stand still time; a rotational speed of the vehicle engine, or one or several parameters which correlate with the engine rotational speed, a new, the same, or a different drive request by the driver, a change in the operating condition of the vehicle, and a plausibility check occurring during the startup procedure.

Growing community of inventors

Nonnenhorn, Germany

Reiner Kneer