This is a much more sophisticated machine, with the power cycler operating the crankshaft and the pump cylinder attached to a pin in the flywheel. Note the sectional view of a later engine in Photo 7. It was cumbersome, using two slide valves and a poppet valve, as well as a second cylinder, but Sir Dugald proved his point, with an engine that produced power on every revolution of the crankshaft.Д¬lerk was an untiring engineer and inventor, and continued improving his engine. In 1880, four years after OttoвЂ™s breakthrough, Clerk secured a U.S. He was successful, but his design required using a separate piston for charging the power cylinder, and he used valves. 12, 1932, in Ewhurst, Surrey, England.Д¬lerkвЂ™s aim was to build an engine that produced power on every down stroke of the piston, and used compression to increase efficiency. Many regard him as the father of that engine. He built gas engines, wrote technical books, and contributed much to the development of the 2-stroke cycle. During World War I he was director of engineering research for the admiralty. A brilliant engineer, he also understood thermodynamics and could calculate engine pressures, temperatures and power. He studied engineering at Anderson College in Glasgow and Yorkshire College of Science in Leeds. Hello, 2-cycle! It was a new idea, one that none had succeeded with before.Д¬lerk was born in Glasgow, Scotland, on March 31, 1854, the son of Donald Clerk, a machinist. Just two years after OttoвЂ™s invention, Clerk modified a Brayton engine to produce power on every revolution of the crankshaft.

Crossing the English Channel to Scotland we meet Dugald Clerk (Photo 5). It was a success, and soon hundreds were being built in Germany, the United Kingdom and the United States.Д«ut, as the saying goes, someone will always try to build a better mousetrap, and hence our tale of the 2-stroke cycle commences.

In 1876, he was ready to market the worldвЂ™s first 4-stroke cycle engine (Photo 4). He had patience, and reasoned that if he compressed the charge, he would get more power. He understood thermodynamics and was aware of the Carnot cycle, a theory of a perfect cycle of efficiency, that can never be achieved. In Germany, Nikolaus August Otto (Photo 3) gave it some deep thought. Atmospheric engines were inefficient, noisy and dangerous, and the power-to-weight ratio was horrible. Neat concept, and many tried, but few succeeded. Picture the barrel as the cylinder and the cannon ball as the piston. Perhaps the first thought of building an engine using explosive power (internal combustion) came from someone watching a cannon fire. I want to explore some of the varied history of the 2-stroke cycle, including who invented it, and how it came about, but first, letвЂ™s take a look at the 4-stroke cycle, as it was invented before the 2-stroke cycle engine. Note that the 4-cycle engine has only one power stroke for every two revolutions of the crankshaft versus the 2-cycle engineвЂ™s power stroke for every revolution of the crankshaft. The diagram in Photo 2 shows this nicely. First, the piston goes down on the intake stroke, then it pushes back up on the compression stroke, then itвЂ™s pushed down again on the power stroke, and finally it goes back up again on the exhaust stroke. One might ask then, what is the 4-cycle engine? Again, the correct term should be вЂњ4-stroke cycle,вЂќ as there are four strokes of the piston to complete one power cycle. The diagram in Photo 1 shows this quite well. We take for granted that they are called 2-cycle, because actually, the term should be вЂњ2-stroke cycle,вЂќ meaning there are two strokes of the piston, one up and one down, to complete a power cycle, with power created on every revolution of the crankshaft.

Just mix some oil into the gas and they do the job. We all know what a 2-cycle engine is, right? ItвЂ™s that little buzzy-sounding engine powering your weed eater or chain saw! They have been around as long as we can remember, and we donвЂ™t give them much thought.

Internal combustion 4 stroke gas