Zf Friedrichshafen Ag

Christian Schwemer

Bernd Allgaier

Peter Schiele

Klaus Steinhauser

Christian Popp

Georg Gierer

Johannes Kaltenbach

Thilo Schmidt

Friedrich Tenbrock

Michael Gromus

Tobias Zollner

Rainer Grundler

Dieter Neumann

Jens Wagner

Martin Neumann

Klaus Habe

Ruben Cüppers

A method for operating a hydraulic system of an automatic transmission, in particular in a hybrid drivetrain, in which the hydraulic system comprises a main pump that is powered by an internal combustion engine and/or an electric drive motor, an electric auxiliary pump and a system pressure valve for setting a system pressure, to ensure various operating functions. In addition to the main pump, the electric auxiliary pump also supplies the hydraulic system with a volume flow of an operating medium. The loading of the electric auxiliary pump is determined in an electronic control unit with regard to the value of the system pressure and the loading of the electric auxiliary pump is limited, by the electronic control unit, with regard to the selected operating function.

Method of operating an auxiliary electric pump

A method for operating a parallel hybrid powertrain () of a vehicle having one internal combustion engine () and one electric motor (). The electric motor is located in the drivetrain between an output and the internal combustion engine. Between the internal combustion engine and the electric motor, a frictionally engaged shifting element is provided, while between the electric motor and the output, a starting element () having a hydrodynamic torque converter (A) and a converter lock-up clutch (B) is disposed. A target output torque to be applied to the output is dependent on the slippage of the starting element. During a starting phase of the internal combustion engine via the electric motor, an input torque produced by the electric motor is directed at least in part via the torque converter and in part via the converter lock-up clutch.

Method for operating a parallel hybrid powertrain of a vehicle with at least one internal combustion engine and at least one electric motor

A method for operating power train side components of a motor vehicle. Using a control device of a motor, at least one motor parameter is issued and delivered via a databus to at least one control device of one other power drive side component working independently of the motor control device in order to operate all or each one of the power drive side components dependent. in a first inventive aspect, a behavior of the respective other power drive side components that adjusts itself according to the motor torque actually made available by the motor is evaluated. In second inventive aspect, the motor torque issued by the motor control device is compared with a torque stored according to motor operation parameters in the control device working independently of the motor control device.

Method for operating drive train side components of a motor vehicle

A braking method for a vehicle is proposed as a safety measure and replacement function if the brake system fails, in particular the X-by-wire brake system of a motor vehicle, in which the vehicle is braked with the help of the transmission by a defined engagement of frictional shift elements until the vehicle comes to rest, such that the combination of frictional shift elements actuated when the vehicle's working brake system fails does not correspond to the shift logic of a gear during normal driving operation of the vehicle.

Braking method for a vehicle

A method for determining an oil condition, namely, an oil condition corresponding to the oil age or oil damage, with the following steps: a) measuring a temperature of the oil or of the part through which the oil flows, coordinating each temperature measured with one temperature range defined by an upper limit and/or a lower limit; b) as soon as the measured temperature exceeds or falls below a limit of a temperature range, measuring the period of time during which the measured temperature dwells in this range; c) in addition, integrating an oil flow running during this time over the time period measured in step b); d) from the time period measured in step b) and the integral of the oil flow determined in step c), determining an oil age or oil damage characteristic for the current temperature range.

Method for determinating of an oil condition

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Friedrichshafen, Germany

Christian Schwemer