Zf Friedrichshafen Ag

Thomas Knoblauch

Matthias Winkel

Marcus Gansohr

Christoph Rüchardt

Klaus Schweiger

Otto Ebner

Andreas Schwenger

A method is proposed for determining a clutch application point in a transmission of a vehicle having a spring-actuated clutch system in which the clutch application point is adapted according to at least one adequate regulated quantity of the clutch system.

Method for determining the clutch application point

A known device for increasing the functional reliability for a hydraulic circuit of a hydraulic clutch having a pressure reservoir () and a release cylinder () which comprises a primary piston () and a secondary piston (). A compensation volume is developed in the sense that when the vehicle is at a standstill and the parking brake released, an unintentional release of the clutch is prevented. A pressure-monitoring/pressure-supply device () is used for determining a reference operating pressure and establishes a static pressure which, in case of any system error, only allows displacement of the secondary piston () such that the contact pressure of the clutch discs, against one another, is still sufficient to maintain the vehicle at a standstill.

Device for increasing the functional reliability of a hydraulic circuit of a hydraulically operable clutch

A method for clutch actuation at low temperatures for a motor vehicle having a hydraulically actuatable clutch, below a predetermined temperature a situation-dependent pre-opening of the clutch is executed when a braking is probable.

Method for actuating a clutch at low temperatures

The invention relates to a method for controlling a pressure supply device in a hydraulic circuit, especially in a hydraulic circuit in an automatic gearbox which comprises an hydraulic pump, a pressure control valve and a consumer. The hydraulic pump is controlled if the system pressure falls below a specific lower threshold value and is switched off if a specific higher threshold value of the system pressure is reached or exceeded. In the data on the system pressure is not available, the current system pressure is calculated.

Method for controlling a pressure supply device in a hydraulic circuit

An operating time is determined by an approximation method within the scope of the method for determining the actual operating time of a hydraulic, electrohydraulic or electric component of a motor vehicle or of a working machine within a reference time or a monitoring period.

Growing community of inventors

Saarbrücken, Germany

Thomas Knoblauch