Internal combustion engine operated with gaseous fuel

摘要

An internal combustion engine operated with gaseous fuel has a quality control and a quantity control. A gas pressure regulator for the gas supply to an air-gas mixer can be activated by a vacuum prevailing in the area of the throttle valve. A control valve acting in the quality control range of an accelerator pedal, the flow cross section of which valve is reduced as the load increases, is arranged in a control line. The ignition timing is adjusted as a function of the accelerator pedal position. In order to obtain a compact control unit which is not susceptible to faults and takes account of all operating conditions, the unit has a pressure characteristic memory to which an internal combustion engine speed and accelerator pedal position signal are fed as input variables and the output variable of which acts on a regulator which triggers a control element. An output signal of a pressure sensor and the signal of the accelerator pedal position are fed to an ignition retardation characteristic memory which with a regulator influences the ignition timing. By means of a logic control unit to which the internal combustion engine speed and accelerator pedal position signal are fed as input variables, an air-bleed valve is actuated in coasting conditions or when the internal combustion engine is over-revved.