Nikolaus August Otto (1832 - 1891), German by nationality , was a travelling salesman and got interested in the Lenoir engine. The Lenoir atmospheric engine ran at 4% efficiency and Otto was contemplating to improve the engine. He , along with Carl Eugen Langen formed the company, NA Otto & Cie to manufacture these engines. This was probably the first engine manufacturing factory in the world.
In 1867, they developed the Otto-Langen atmospheric engine which won many awards and contracts.
The 1867 Otto-Langen atmospheric engine -
This engine could produce power in the range of 0.25 HP to 3 HP. The exploding combustion of the gas lifted the piston, creating a partial vacuum The piston is returned back to its position by gravity, in the process doing work. The limitation of this engine to go beyond 3 HP was due to the design which requires headroom for this engine. Watch a video of of the Otto-Langen engine working - (Click Here)
In 1869, they moved the company to the town of Deutz and renamed their company as Gasmotoren - Fabrik Deutz.
In 1872, the management brought in Gottileb Daimler as the factory manager and Wilhelm Maybach as the design director.
Nikolaus Otto and Eugen Langen continued to work in trying to improve the efficiency of the atmospheric engine. In 1876 , they developed the first successful 4-cylinder , compression engine, running on illuminating gas (coal gas). The thermodynamic cycle came to be known as Otto cycle and the engine "Gas Engine". Later on the engine was modified to run on Petrol (gasoline) but the name "Gas Engine" stuck on and even now Petrol engines are referred as Gas Engines.
The Otto Cycle - also referred to as the Constant Volume cycle -
Nikolaus Otto wanted to concentrate on large stationary engines where as Gottileb Daimler wanted to concentrate on small automobile engines. This led to Gottileb Daimler quitting the company in 1882, taking Wilhelm Maybach along with him to form his own company - Daimler AG as we know today.
In 1886 , Nikolaus Otto lost his patent right of the Otto engine over recently discovered 1862 patent of Alphonse Beau de Rochas. This engine design was similar to Nikolaus Otto's design but was only on paper. This led to many companies manufacturing Otto cycle engines.
During the war , the company was renamed as Klockner Humbolt Duetz AG (KHD) and later as Deutz AG.
Some the well known Automotive legends have worked in Deutz AG before moving out and starting their own companies - Gottileb Daimler, Wilhelm Maybach, Prosper L'Orange, Rudolf Diesel, Robert Bosch, Ettore Bugatti.
The Deutz AG logo -