4 Stroke engine

                                           

   How to Four Stroke Engine Work?

Almost all cars currently use what is called a four-stroke combustion cycle to convert gasoline into motion. The four-stroke approach is also known as the Otto cycle, in honor of Nikolaus Otto, who invented it in 1867.A four-stroke engine (also known as four-cycle). As you see in this picture that how to 4 stroke engine works.

A four stroke engine works in 4 step which is as following.
    1.Intake stroke
    2.Compression stroke
    3.Combustion stroke
    4.Exhaust stroke

The piston starts at the top (TDC), the intake valve opens, and the piston moves (BDC) down to let the engine take in a cylinder-full of air and gasoline. This is the intake stroke. Only the tiniest drop of gasoline needs to be mixed into the air for this to work.
    Then the piston moves back up (TDC) to compress this fuel/air mixture. Compression makes the explosion more powerful.
    When the piston reaches the top (TDC) of its stroke, the spark plug emits a spark to ignite the gasoline. The gasoline charge in the cylinder explodes, driving the piston down.
  Once the piston hits the bottom of its stroke, the exhaust valve opens and the exhaust leaves the cylinder to go out the tailpipe.
Now the engine is ready for the next cycle, so it intakes another charge of air and gas.

Components of  4 stroke engine  

C: Crankshaft 
E: Exhaust camshaft 
I: Inlet camshaft 
P: Piston 
R: Connecting rod 
S: Spark plug 
V: Valves. Red: exhaust, Blue: intake 
W: Cooling water duct

Crankshaft
                   The crankshaft, sometimes abbreviated to crank, is the part of an engine that translates reciprocating linear piston motion into rotation. To convert the reciprocating motion into rotation, the crankshaft has "crank throws" or "crankpins", additional bearing surfaces whose axis is offset from that of the crank, to which the "big ends" of the connecting rods from each cylinder attach.

Exhaust camshaft
                               A camshaft is a shaft to which a cam is fastened or of which a cam forms an integral part. Exhaust camshaft connected with crankshaft by time built.The exhaust camshaft is use to open the exhaust value to exhaust all gases for engine cylinder.

Inlet camshaft 

                         A camshaft is a shaft to which a cam is fastened or of which a cam forms an integral part. inlet camshaft connected with crankshaft by time built.The inlet camshaft is use to open the intake value to in air fuel mixturer into cylinder.  

Piston
            A piston is a part of a internal combustion engine. The piston goes up and down in a cylinder. When it is up gas is injected and ignited by the spark plug. That explodes and pushes the piston down. The piston is connected to a connecting rod and crankshaft in a way that as it goes down it turns the shaft. The same thing happens to the other pistons in a very quick and repeated process.

Connecting rod 
                          One of the most important features in machinery is the connection rod, because it connects the pistons with the crankshaft. The connection rod links together the movements of both units, even though they differ from one another. The pistons move in a corresponding way whereas the crank turns around an axis in a rotating movement.

 Spark plug
                   A spark plug  is a device for delivering electric current from an ignition system to the combustion chamber of a spark-ignition engine to ignite the compressed fuel/air mixture by an electric spark, while containing combustion pressure within the engine.

                       





Exhaust valve
                         Through Exhaust  valve  all burned gases from a cylinder escape into the exhaust manifold.

Intake valve
                        Through intake valve all flue mixture in from intake manifold into a cylinder. 



Almost all new car having four stroke engine.like the new honda accord having in 4-line 4 Cylinder 4 Stroke engine.More specifications you can see in this table.

In 1982, the Accord became the first car from a Japanese manufacturer to be produced in the United States when production commenced in Marysville, Ohio at Honda's Marysville Auto Plant. The Accord has achieved considerable success, especially in the United States, where it was the best-selling Japanese car for fifteen years (1982–97), topping its class in sales in 1991 and 2001, with around ten million vehicles sold.