Abstract: A sparking plug with a central electrode insulated in respect of the plug screw-thread and with earth electrodes which are electrically connected to the plug screw-thread, there being at the combustion chamber end of the central electrode an attachment part which consists at least partially of platinum or a platinum alloy, the spark gaps being disposed between it and the earth electrodes which extend to it from the side. According to the invention, the attachment part takes the form of a prism, the top surface of which faces the combustion chamber. Furthermore, the earth electrodes extend laterally alongside the side faces of the substantially prismatic attachment member parallel with the edges of top or base surfaces of the prism. This ensures considerable stability and low burn-off. Furthermore, the electrode gap can easily be adjusted.

Abstract: An arrangement for regulating the combustion air mixture in the case of a gas engine operating on a lean fuel, and in the induction line of which there is an air-gas mixer, a lambda regulator being provided and following which there is, for varying the combustion air proportions, a positioning device which adjusts the air-gas mixer, and also an output measuring device for ascertaining the engine output. A manometer determines the actual value of the mixture pressure upstream of the inlet valves of the engine, linked with the value for the combustion air proportions. By adjusting the combustion air proportions, it is possible to regulate the mixture pressure to the output dependent desired value for the mixture pressure as ascertained in a device within the lambda regulator.

Abstract: An ignition device for multi-cylinder internal-combustion engines comprising at least one spark plug for each cylinder. Each spark plug is arranged in the secondary circuit of an ignition transformer. The primary circuits of the ignition transformers are connectable with a source of energy by an ignition distributing circuit.