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- Gasoline Engine
-
- Gasoline engine is defined as "any class of internal combustion
- engines that generate power by burning a volatile liquid fuel with
- ignition initiated by an electric spark".
-
- The most widely used engine is the gasoline engine. Besides being
- the most widely used engine for automobiles, the gasoline engine is
- commonly used in trucks, motorcycles, tractors, boats and small power
- tools such as snow blowers, chain saws, and lawn mowers. Gasoline
- engines vary in size and power. Some of the smaller engines are used
- in models and generate less than one horsepower while some gasoline
- engines generate as much as 35,000 horsepower.
-
- Gasoline engines vary in size, shape, and power but their principles
- of operation are the same. The principle of operation of most
- gasoline engines is the reciprocating-piston. The reciprocating
- piston engine can be sub-divided into two categories, two-stroke and
- four-stroke.
-
- In automobiles the four-stroke is the most common. In the
- four-stroke engine the cylinder cycles four times. The first cycle
- extends the piston and an intake valve opens allowing fuel air
- mixture into the cylinder. The second cycle ascends for the
- compression stroke. In the third cycle the fuel air mixture is
- ignited creating power and in the fourth stroke the exhaust valve is
- opened releasing the spent gasses.
-
- The two-stroke engine completes the cycle of the engine with one
- up-stroke and one down-stroke. Because of the less movement and
- power generated per revolution the two-stroke engine can be made
- lighter and generate more power. However, the two-stroke engine does
- not burn fuel as efficiently and creates more pollution.
-
- The principle for the four-stroke gasoline engine is attributed to
- the French engineer Alphonse Beau de Rochas in 1862. The prototype
- of the modern automobile was developed in 1876 by the German engineer
- Nikolaus Otto. Otto used the principles of Rochas when constructing
- his engine. It wasn't until 1878 that the two cycle engine was
- developed by Sir Dougald Clerk and it wasn't until a simplified,
- workable, more efficient version was introduced by John Day.
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