In 1876, an earth-shattering technical idea was made reality: the German mechanical engineer, Nicolaus August Otto, built the first four-stroke cycle engine. The “induction, compression, ignition and exhaust” principle which he applied to his combustion power machine continues to be applied, unchanged, in engine manufacture today.

The first functional combustion engine had already been constructed by the Belgian Etienne Lenoir in 1859. The gas engine, which was similar to a horizontal steam engine, worked with a mixture of illuminating gas and air. The movement of the piston sucked the gas mixture into the cylinder where it was ignited with an electric spark. The explosion moved the piston back again. On the way back, the combustion gases were expelled whilst on the other side of the piston, the induction and working process was repeated.

In 1867, Nicolaus August Otto developed an improved engine, the so-called free piston atmospheric engine. The motor was awarded the gold medal at the World Fair in Paris in 1867 despite the noise it made during operation. The fact that its fuel consumption was around 60 percent more favorable than the engines produced by other manufacturers proved decisive.

In the spring of 1876 the “Otto engine” followed. This was a four-stroke gas engine with compressed charge which was initially driven with the aid of a gas flame as an external source of ignition. Shortly before the end of the piston stroke during the compression phase, the flame is introduced into the cylinder where it ignites the air-fuel mix, for which it was, however, only possible to use gaseous fuels. The basic principle was and remains simple: fuel is drawn in, compressed and then combusted. In the fourth stroke, the combusted gasses are then expelled.

Within a very short space of time Otto’s “new engine” was developed further by Maybach until it was ready for series production, being introduced onto the market in 1876 under the name “Deutzer A-motor” with an approximately 3 horsepower engine. As early as the following year, engine power could be increased to 5 horsepower.

In 1883, Otto finally built an engine which also ran on petrol. Karl Benz perfected the four-stroke cycle engine and presented the first automobile in 1886.