Bayerische Motoren Werke Aktiengesellschaft

Georg Meder

Gerd Kraemer

Ralf Cosfeld

Till Scheffler

Gert Rekewitz

Stefan Uhl

Tim Beattie

Florian Albrecht

Franz Bichler

Franz Kofler

Johann Hofmann

Wolfgang Heinle

Florian ÖSterreicher

Emanuel Fuchs

Axel PÖLTENSTEIN

Gerd KRÄMER

The invention relates to a method for automatically switching off an internal combustion engine in a motor vehicle, in particular in a motor vehicle having an automatic transmission, by means of a stop/start device, which initiates measures for automatically switching off the internal combustion engine if the vehicle has been braked to a stop and advantageously held at a stop by actuation of the brake pedal for a predefined time interval. The invention is characterized in that the rotation speed of the internal combustion engine is changed, in particular reduced, at a defined point in time before the measures for automatically switching off the internal combustion engine are initiated.

Method for automatically switching off an internal combustion engine

An electronic control device according to the invention is disclosed for controlling the internal combustion engine in a motor vehicle, for fault recognition with an irregular running determination unit and with an injection quantity correction unit, a defined group of cylinders being associated with a lambda probe, the injection quantity of a cylinder to be investigated of the defined group is adjusted in the direction of lean by a differential adjustment value associated with an irregular running differential value, and the injection value of at least one of the remaining cylinders, which are associated with the same lambda probe, is correspondingly adjusted in the direction of rich, so that in total a predetermined lambda value of this group of at least approximately 1 is reached. Homogeneous operation is thus ensured. The differential adjustment values may, for example, relate to the injection quantity itself, the injector stroke or the injection time. In this manner, a differential adjustment value individual to the cylinder is adjusted for each cylinder of the defined group. Correction values individual to the cylinder are then determined in that the differential adjustment values individual to the cylinder are related to one another.

Electronic control device for controlling the internal combustion engine in a motor vehicle

In a process and a device for electronically controlling actuators of a combustion engine with variable gas exchange control using a suction pipe pressure model where the connection between the cylinder filling level and the suction pipe pressure is described by a straight line with gradient and offset, the gradient and/or offset are determined as a function of the valve overlap surface. Preferably, the gradient and/or the offset are also determined as a function of the position of the valve overlap surface. The position of the valve overlap surface can be determined by the interval between the center of gravity of the valve overlap surface and a reference crankshaft angle. This improves the control of a combustion engine in motor vehicles with a gas exchange control (for example, with variable cam shaft rotation and/or cam shaft switchover to phaseless change of the valve control time and/or the valve stroke) with a view to accuracy and flexibility.

Process and device for electronically controlling actuators of a combustion engine with variable gas exchange control

Cylinder-selective control of the air-fuel ratio in a multi-cylinder internal-combustion engine is provided, wherein a lambda probe arranged in the exhaust pipe system generates a voltage signal corresponding to an air-fuel ratio. The voltage signal is supplied to a computing unit which determines the air-fuel ratio for each individual cylinder. A fuel metering unit determines a fuel injection quantity at least as a function of a basic fuel injection value and the determined air-fuel ratios of the individual cylinders, and a fuel supply unit supplies the fuel injection quantity determined by the fuel metering unit to the cylinders of the internal-combustion engine. The computing unit crank-angle-synchronously detects the voltage signal and assigns it to a certain cylinder. A voltage deviation and corresponding injection quantity correction is determined for each cylinder in relation to the voltage signals of the adjacent cylinders.

Cylinder-selective control of the air-fuel ratio

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Munich, Germany

Georg Meder