Zf Friedrichshafen Ag

Andreas Wolf

Matthias Winkel

Bertram Wengert

Christoph R&uuml;chardt

J&uuml;rgen M&uuml;ller

Rainer Petzold

Rupert Kramer

Ulrich Reith

Wolfgang Gröner

Reinhard Mertinkat

Gerd Sauermann

Klaus Hensinger

Jerome Lochard

Michael Buckhart

A device and a method for control of an automatic transmission () in a vehicle having one control unit (), which can receive signals produced by a transmission gearshift lever (), and/or a first transmission control (). The signals of the first transmission control are bridgeable so that the automatic transmission can be manually operated. In order to make it possible to efficiently operate the vehicle with low fuel consumption and great flexibility of the driver at the moment, manual operation of the automatic transmission is possible only when the vehicle is at speed (v) lower than a predetermined speed limit.

Device and method for controlling an automatic transmission in a motor vehicle

A method for controlling a partially unsynchronized manual transmission, which realizes the increase of a rotational speed of a transmission part to be synchronized during a gear change procedure by connecting one element of the transmission, via a shiftable clutch, to a drive motor and by making available to this drive motor the required rotational speed as well as the necessary torque at its output shaft. It is also provided that when the rotational speed and/or the torque made available by the drive motor is not sufficient to ensure the synchronization of the manual transmission within a fixed time period, a shifting strategy is pursued, which prevents an unintentional holding of the manual transmission in its neutral position or idle position.

Method for controlling a manual transmission in the event of a disorderly engine behavior

The method for determining the mass of a vehicle comprises at least two measurements ( ) offset in time within a measuring period by which are determined respectively at least one traction variable ( ) and at least one movement variable ( ) of the vehicle, one of the two measurements ( ) being effected during a traction-free phase and the other of the two measurements ( ) during a traction phase. According to the invention, it is proposed that each of the two measurements comprises one data collection period ( ) the duration of which is longer than a minimum duration, that the traction variable corresponds to the timed integral of the traction and the movement variable to the change of speed of the vehicle.

Method and device for determining the mass of a vehicle

The invention relates to a method for determining a starting gear step for a vehicle with a stepped variable speed transmission with several gear steps. It is proposed that a maximum admissible value for a slip time ( ) and/or a maximum admissible value for a frictional work ( ) of the starting clutch during the starting process, the same as an available engine torque ( ) for starting be determined, that beginning with a highest suitable gear step ( ) for starting, values for the slip time ( ) and/or the frictional work ( ) be calculated in advance depending on the vehicle mass ( ), that the precalculated values ( ) be compared with the maximum admissible values ( ), that the calculation loop be repeated with the next smaller suitable gear step for starting when at least one of the precalculated values is greater than the maximum admissible values and that a gear step be issued as starting gear step when the precalculated values are smaller than or equal to the maximum admissible values.

Method for determining a starting gear step

The invention relates to a method for detecting cornering for a vehicle ( ) with automatic transmission. According to the invention it is proposed that the current bend radius be determined from the rotational speed signals of the front wheels, that the beginning of a cornering mode be determined when the current bend radius falls below a first limit bend radius and the end of a cornering mode be determined when the vehicle has covered a presettable distance after exceeding a second limit bend radius.

Method for detecting cornering for a vehicle with an automatic transmission

The invention relates to a method for determining a starting gear step for a vehicle with a multi-speed stepped variable transmission, wherein the starting gear step is determined by an electronic control device which is dependent on the vehicle mass; and a second variable which depends on the vehicle state is determined from the vehicle mass, the current traction and the current vehicle acceleration resulting therefrom.

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Ravensburg, Germany

Andreas Wolf