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Four-stroke engine

technology Maturity 11-13 Next article →

A four-stroke engine is a type of internal combustion engine. This means it burns fuel inside the engine to create power. These engines are very common in our world today. You can find them in cars, trucks, and motorcycles. They are also used in light aircraft and even diesel trains.

Ciclo del motore 4T
Ciclo del motore 4T

This engine design is a major way we move people and things across land. It works by using a piston that moves up and down inside a cylinder.

The engine works through a way of working called a cycle. It has four separate steps, which are called strokes.

Four stroke cycle intake
Four stroke cycle intake

First is the intake stroke. The piston moves down to pull an air-fuel mixture into the cylinder. Next is the compression stroke.

Four stroke cycle compression
Four stroke cycle compression

The piston moves back up to squeeze that mixture tightly.

Four stroke cycle spark
Four stroke cycle spark

Third is the power stroke. A spark plug ignites the fuel, which pushes the piston down with force. This force turns a part called the crankshaft. Finally, the exhaust stroke happens.

Four stroke cycle exhaust
Four stroke cycle exhaust

The piston moves up to push the used air out through an exhaust port.

People have been working on these engines for a long time. In 1860, a man named Jean Joseph Etienne Lenoir built an engine in Paris. It ran on illuminating gas and had only 2 horsepower.

PSM V18 D500 An american internal combustion otto engine
PSM V18 D500 An american internal combustion otto engine

Later, Nicolaus Otto studied how compression could make engines better. In 1876, Otto and his partner Langen created an engine that compressed fuel for much higher efficiency. This was a huge step forward for technology. Other famous names like Gottlieb Daimler and Wilhelm Maybach also helped develop high-speed engines.

There are different kinds of these engines with different jobs.

T cycle AtkinsonMiller
T cycle AtkinsonMiller

James Atkinson invented a special version in 1882 called the Atkinson cycle. It is designed to be very efficient, so it is used in some modern hybrid cars like the Toyota Prius.

Another type is the diesel engine. Rudolf Diesel wanted an engine that could use heavier fuel. He created a successful high-compression engine in 1893.

1 Audi R15
1 Audi R15

Diesel engines are often used for heavy-duty jobs because they are very strong.

Understanding engines helps us see how our machines work. Most of the vehicles you see on the road rely on these cycles. The power of the engine depends on how much air it can take in. It also depends on the speed, or RPM, of the engine.

diagrama pv de ciclo 4tempos
diagrama pv de ciclo 4tempos

Engineers must also think about the fuel used. For example, gasoline has an octane rating to show how it resists igniting too early. This helps keep the engine safe and working well. It is amazing how these small movements create so much movement in our world.

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🖼️ Images & Media (13)
File:4StrokeEngine Ortho 3D Small.gif
4StrokeEngine Ortho 3D Small.gif
File:PSM V18 D500 An american internal combustion otto engine.jpg
PSM V18 D500 An american internal...
File:Prius2004.JPG
Prius2004.JPG
File:T cycle AtkinsonMiller.png
T cycle AtkinsonMiller.png
File:1 Audi R15.jpg
1 Audi R15.jpg
File:diagrama pv de ciclo 4tempos.png
diagrama pv de ciclo 4tempos.png
File:Ciclo del motore 4T.svg
Ciclo del motore 4T.svg
File:Four stroke cycle start.png
Four stroke cycle start.png
File:Four stroke cycle intake.png
Four stroke cycle intake.png
File:Four stroke cycle compression.png
Four stroke cycle compression.png
File:Four stroke cycle spark.png
Four stroke cycle spark.png
File:Four stroke cycle power.png
Four stroke cycle power.png

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