Internal Combustion Engine without Compression Stroke
The history of the combustion engines does not start with the Otto engine, but roughly 100 years earlier with the steam engine and its direct predecessor, the internal combustion engine without compression. In 1862 there was the idea to build a four stroke engine, but the technical abilities for the compression of the air-illuminating gas-mixture was not sufficient yet. Thus, Nicolaus August Otto and Eugen Langen came up with the internal combustion engine without compression, which they started producing in 1864 for twelve years. It has its origins in the illuminating gas engine of 1860 by Lenoir in Paris.
How it works
The combustion and pressure initiation takes place outside the piston casing for the steam engine, and inside for the internal combustion engine without compression. In comparison with the Otto engine it lacks a compression stroke. Here, a mixture of air and fuel or illuminating gas is ignited by heat and the piston is moved to its top dead center (TDC). It does not transmit its power via a crankshaft and a connecting rod, but via a gear rack with a kind of free-wheel onto a large fly-wheel. From the fly-wheel the power was transmitted throughout the factory via belt drives. Subsequently, the piston moves to its bottom dead center, just by its own weight, without compressing an air-fuel mixture. The combustion chamber is decreased by roughly one tenth. Only then, the new air-fuel mixture is launched and ignited. This explains the name, as there is no pressure in the combustion chamber. 01/10