Abstract: A method for operating an internal combustion engine having a fuel system which feeds fuel at a given pressure to a metering valve provides that a controller defines the opening time and the closing time of the metering valve and correspondingly actuates the metering valve so that the metering valve opens and closes at the defined times. In order to permit precise metering of fuel even in high-speed internal combustion engines there is provision for the controller to define at least one of the times for the opening or closing of the metering valve while taking into account the counterpressure actually prevailing at the outlet opening of the metering valve.

Abstract: The absolute crankshaft angle of an internal combustion engine of a hand-held power tool is to be determined. The engine has a cylinder with a combustion chamber delimited by a piston that drives a crankshaft in a crankcase. The crankcase is connected by a transfer passage to the combustion chamber and the transfer port of the transfer passage is piston-controlled. Ignition takes place at an adjusted crankshaft angle. The energy supply unit of the engine is driven by the crankshaft and provides electric energy for ignition. The crankshaft angle is determined in that a signal generator is provided as an energy supply unit and generates an alternating voltage signal caused by a crankshaft revolution. An operating pressure signal of the engine is detected by a pressure sensor. The output signals of the pressure sensor and of the signal generator are linked with one another for determining the absolute crankshaft angle.

Abstract: A method for operating an internal combustion engine having a fuel system which feeds fuel at a given pressure to a metering valve provides that a controller defines the opening time and the closing time of the metering valve and correspondingly actuates the metering valve so that the metering valve opens and closes at the defined times. In order to permit precise metering of fuel even in high-speed internal combustion engines there is provision for the controller to define at least one of the times for the opening or closing of the metering valve while taking into account the counterpressure actually prevailing at the outlet opening of the metering valve.

Abstract: The absolute crankshaft angle of an internal combustion engine of a hand-held power tool is to be determined. The engine has a cylinder with a combustion chamber delimited by a piston that drives a crankshaft in a crankcase. The crankcase is connected by a transfer passage to the combustion chamber and the transfer port of the transfer passage is piston-controlled. Ignition takes place at an adjusted crankshaft angle. The energy supply unit of the engine is driven by the crankshaft and provides electric energy for ignition. The crankshaft angle is determined in that a signal generator is provided as an energy supply unit and generates an alternating voltage signal caused by a crankshaft revolution. An operating pressure signal of the engine is detected by a pressure sensor. The output signals of the pressure sensor and of the signal generator are linked with one another for determining the absolute crankshaft angle.