Zf Friedrichshafen Ag

Thomas Hafen

Mario Steinborn

Josef Bader

Martin Miller

Andreas Graf

Ingo Sauter

Jochen Breuer

Melchor Moro-Oliveros

Wolfgang Gröner

Andelko Vesenjak

A method of decoupling a power take-off drive of a motor vehicle transmission during travel of a motor vehicle in which a form-locking shift element of the power take-off drive is controlled for disengaging the power take-off drive. To implement reliable decoupling without interrupting travel of the motor vehicle, if disengagement of the shift element initially did not occur, control of the shift element is immediately implemented the next time a separating clutch, placed between the motor vehicle transmission and a drive engine of the motor vehicle, is actuated and/or a connection of the shift element toward an output side of the motor vehicle transmission is interrupted, over the course of a subsequent gear shift in the motor vehicle transmission. A drive train of a motor vehicle, a computer program product, and a data carrier having the computer program product.

Method for decoupling a power take-off of a motor vehicle transmission while driving a motor vehicle

A method of operating a drivetrain of a motor vehicle. The drivetrain comprises a transmission arranged between a drive assembly and an axle drive, such that an input shaft of the transmission is connected, via a controllable separator clutch, to the drive assembly and an output shaft of the transmission is connected to the axle drive, and such that the transmission comprises at least one shifting element formed as a claw clutch. To reduce the probability that a tooth-on-tooth position may occur in a shifting element formed as a claw clutch, a torque is applied thereto by at least one transmission-internal assembly and/or at least one transmission-external assembly so that a speed difference at the claw clutch approaches a predetermined nominal value, and engagement of the claw clutch is only started when the speed difference of the claw clutch reaches the nominal value.

Method for operating a drive train

A method for shifting an automated transmission situated in a drive train of a motor vehicle between an engine and a drive axle and having at least one multi-speed main transmission and a two-speed range change group rear-mounted thereon. The main transmission has at least one counter shaft with a transmission brake. A clutch engages the prime mover and the main transmission and the range change group is shifted via unsynchronized dog clutches which are combined in pairs in a common shift set and have two shift positions and one neutral position such that, during a range change gear shift both in the main transmission and the range change group a change between two ratio stages occurs. A range change up-shift includes synchronizing the input shaft and the target gear utilizing the transmission brake and passively synchronizing the dog shifted transmission parts by the edge beveling of the concerned dog clutches.

Method for shifting actuation of an automated group transmission

A method for shifting an automated transmission situated in a drive train of a motor vehicle between an engine and a drive axle and having at least one multi-speed main transmission and a two-speed range change group rear-mounted thereon. The main transmission has at least one counter-shaft with an transmission brake. A clutch engages the prime mover and the main transmission and the range change group is shifted via unsynchronized dog clutches, which are combined in pairs in a common shift set having two shift positions and one neutral position such that during a range change gearshift, both in the main transmission and in the range change group, a change between two ratio stages occurs. A range change up-shift and down-shift each include active synchronization of the dog clutch by way of the transmission brake and of the separating clutch.

Method for shifting actuation of an automated transmission

A shift control method of a range group transmission with a multi-speed main transmission, which connects with a drive motor, via a clutch (K) and an input shaft. A transmission brake optionally engages the input shaft. At least a two range group is located downstream of the main transmission. A range change shift is accomplished by changing a gear of the main transmission and the range group. The shifting sequence is accelerated by: reducing motor torque and disengaging the clutch (K); disengaging a previous range group gear; synchronizing a new range group gear; disengaging a previous main transmission gear; engaging the new range group gear; synchronizing a new main transmission gear; engaging the new main transmission gear; and engaging the clutch (K) and increasing the motor torque, such that synchronization of the new gear occurs by influencing the input shaft of the main transmission.

Growing community of inventors

Salem, Germany

Thomas Hafen