Karl Benz filed for a patent on his first reliable two-stroke gas engine in 1878

 

On 31 December 1878, Karl Benz, working in Mannheim, Germany, filed for a patent on his first reliable two-stroke gas engine. He was granted the patent in 1879.

A two-stroke, engine is a type of internal combustion engine that completes a power cycle with two strokes (up and down movements) of the piston during one power cycle, this power cycle being completed in one revolution of the crankshaft. A four-stroke engine requires four strokes of the piston to complete a power cycle during two crankshaft revolutions. In a two-stroke engine, the end of the combustion stroke and the beginning of the compression stroke happen simultaneously, with the intake and exhaust (or scavenging) functions occurring at the same time.