Reading Materials

Passage 1

Structure of Automobile

Today's average car contains more than 15,000 separate, individual parts that must work together.These parts can be grouped into four major categories:engine, chassis, body and electrical system.

Engine

Today, the four stroke cycle internal combustion engines are commonly used in cars, trucks, motorcycles and many others other transport vehicles.The four strokes refer to intake, compression, combustion and exhaust strokes that occur during two crankshaft rotations per working cycle of Otto Cycle.

The engine provides power to move the automobile.The most common type of automotive engine is the gasoline-burning engine.It is found in most automobiles.Diesel-fuel burning engines are also used in modern passenger cars, as well as in large trucks.All en-gines have fuel, exhaust, cooling, and lubrication systems.Gasoline engines also have an ignition system.

Chassis

A chassis which is considered as a support frame for an auto body is used to assemble all auto spare parts on it.In fact, when power from engine continues to be transmitted to chassis, it begins with power train, and goes on to steering, wheel suspension, brakes and tires.These individual components interact with each other closely.

Body

The automobile body which is regarded as the framework is seated on the chassis.Its function is obvious for occupants to provide comfort, protection and shelter.The automobile body is generally divided into five sections:the front, the upper and and top, rear and the underbody.Theses sections are further divided into small units, such as the hood, the fender, the roof panels, the door, the instrument panel, the bumpers and the luggage compartment.

The Electrical System

The electrical system is considered an auto electric power source supplying lighting power for the automobile.The electrical system contains battery, lights, generator, engine ignition, lighting circuit, and various switches that control their use.