Abstract: A fuel injection system for internal combustion engines is proposed which supplies fuel injection valves with fuel from a high-pressure fuel source, under the control of a control unit. The fuel injection valve has an injection valve member, whose opening or closing position is determined by a pressure that acts upon this injection valve member and that is set in a control chamber. To that end, to perform an injection, the pressure in the control chamber must be relieved; which is achieved with a control valve that opens two different outflow cross sections of an outflow conduit of the control chamber in succession. This makes it possible to accomplish an adapted opening of the fuel injection valve member for a preinjection and for a main injection.

Abstract: A valve for controlling fluids, in which the valve member is adjusted by means of an actuating piston, which, together with a piezoelectric actuator piston, encloses a pressure chamber. In addition, the actuator piston and an affiliated piezoelectric stack are disposed in parallel radially next to the actuating piston, wherein upon excitation of the piezoelectric stack or adjustment of the actuator piston, the actuating piston executes a motion counter to the adjusting movement, and with its valve member, opens a relief bore.

Abstract: An apparatus for measuring particulate matter in a flue gas or exhaust gas of a combustion process comprising means for transmitting a beam of light between an optical transmitter and an optical receiver. The light passes through two diametrically opposed light slits closed by transparent bodies in the wall of the tail pipe and crosses through a flow of exhaust gas carried in the tail pipe. The attenuation of intensity of the light beam is a measure of the particulate matter. When the measuring apparatus is used to measure a soot concentration in an exhaust gas of internal combustion engines of a vehicle, it is mounted directly on the tail pipe, and the transparent bodies are heated in the vicinity of the faces acted upon by the exhaust gas flow to a temperature above the soot burn-off temperature. As a result, adulteration of the measured value by soot deposits in the measurement path to the transparent bodies is prevented, and continuous operation of the measuring apparatus is assured.

Abstract: A device for measuring particle emissions of an internal combustion engine, in particular the soot concentration in the exhaust gas, has a signal transmission route, located between a transmitter and a receiver, which traverses a flow of exhaust gas carried in an exhaust gas tube of the engine. To avoid soiling of the active elements of the transmitter and receiver that would cause inaccuracies in measurement, the signal transmission route is embodied as a beam of light, which passes through two diametrically opposed openings in the wall of the exhaust tube. The light-admitting openings are each closed with a respective transparent disk. The disks are heatable and are heated to a temperature above the burnoff temperature of the particles. Appropriate light emitting and receiving elements are used in combination with appropriate heating and evaluation circuits which indicate the soot concentration and which control fuel input to change the soot concentration.