Zf Friedrichshafen Ag

Friedrichshafen Ag

Holger Bacher

Tobias Zollner

Armin Gierling

Bernd Allgaier

Stefan Sommer

Frank Deprez

Clemens Kuhn

Patrick Peter

Jens Kastens

Bernhard Fessler

Klaus Gessler

Tobias Zöllner

Lorenz Fehrenbach

Dirk Clausen

Jakob Scholz

A method for operating a hybrid vehicle having a prime mover including an internal combustion engine and an electric machine, the vehicle further having a transmission connected between the prime mover and a driven end and including multiple shift elements, the vehicle further having a separating clutch connected between the internal combustion engine and the electric machine, and a starting component which is provided by a separate launch clutch or by a shift element of the transmission. The method includes monitoring a rotational speed of one of the internal combustion engine, the electric machine, the transmission, or the driven end during travel with the internal combustion engine running and the separating clutch engaged. The method further includes determining an increase in driving resistance, and decoupling the internal combustion engine when the monitored rotational speed falls below or reaches a first limiting value by disengaging the separating clutch.

Control method and control unit for a hybrid vehicle

A method of controlling a hybrid drive-train of a vehicle having a combustion engine with a driveshaft, a transmission with an input shaft and an output shaft that drives a transfer box. An electric machine has a rotor that is connected to the transmission input shaft. A separator clutch is arranged between the engine driveshaft and the transmission input shaft. For coupling of the engine, the engine is first accelerated, with a rotational speed regulation, toward a target speed until a reference speed is reached or exceeded while the clutch remains disengaged, then, with continuous speed regulation, the engine is adjusted to a corrected target speed while the clutch is engaged until a target torque is obtained, then, with torque control, the engine is adjusted to the target torque while the clutch, with differential rotational speed regulation, is regulated to a target speed difference, and finally the clutch is engaged.

Method for controlling a hybrid drive train of a motor vehicle

A method of operating a drive-train of a hybrid vehicle which comprises at least a hybrid drive with an internal combustion engine and an electric machine, an automatic or automated change-speed transmission connected between the hybrid drive and a drive output, and a clutch connected between the internal combustion engine and the electric machine. When starting the internal combustion engine from a purely electric driving mode, the clutch is initially disengaged. To start the internal combustion engine, the clutch is at least partially engaged and the internal combustion engine is drag-started by the electric machine, and, in parallel with starting the internal combustion engine, a downshift in the transmission is initiated once a rotational speed of the internal combustion engine reaches or exceeds an applicable threshold value.

Method and control unit for operating a drive train of a hybrid vehicle

The proposal is for a process for controlling a CVT of the bevel-pulley-belt type in which, on the occurrence of a wheel-locking drive situation, a converter bridging clutch is disengaged and at the same time a forward or reverse drive clutch is disengaged. The pressure level of the secondary pulley ( ) is hereby raised and the transmission ratio of the CVT is changed in accordance with a predeterminable transmission ratio change and a predeterminable gradient.

Process for controlling a continuously variable transmission system (CVT)

The invention is based on an electronic-hydraulic control unit ( ) for an automatic transmission of a motor vehicle wherein the control unit ( ) has one hydraulic unit ( ) with hydraulic valves ( ), sensors ( ) and pressure regulators ( ) and one electronic unit ( ) with a microprocessor, memories, sensors and power regulators ( ) which form a functional unit. To reduce the tolerances of the control unit, it is proposed that the pressure tolerances appearing in the operating range be detected by verifying characteristic lines and from the divergences relative to a set characteristic line, plotting and storing in a memory a corresponding characteristic line correction.

Electronic-hydraulic control unit for an automatic transmission for vehicles

CVT control method

Growing community of inventors

Lindau, Germany

Holger Bacher