車輛工程專業(yè)英語概述.docx

The Principal Components Of Automotive張可可2013210612 The Principal Components Of Automotive contains the body, the engine , the chassis , the power train system, the steering system, the suspension system and wheels , the braking system and the electrical and electronic system.1 The body An automobile body is a sheet metal shell with windows, doors, a hood and a trunk deck built into it. It provides a protective covering for the engine, passengers and cargo. It is designed to keep passengers safe and comfortable. The body styling provides an attractive, colorful, modern appearance for the vehicle.2 The engine The engine acts as the power unit. The internal combustion engine is most common: this obtains its power by burning a liquid fuel inside the engine cylinder. There are two types of engine: gasoline (also called a spark-ignition engine) and diesel (also called compression-ignition engine). Both engines are called heat engines. the burning fuel generates heat which causes the gas inside the cylinder to increase its pressure and supply power to rotate a shaft connected to the power train.3 The chassis Chassis is the frame on which the engine, body, wheels etc. are built. The chassis is an assembly of those systems that are the major operating parts of a vehicle. It includes power train which conveys the drive to the wheels, steering which controls the direction of movement，suspension and wheels which absorb the road shocks, and brake which slows down the vehicle.4 The power train system The power train transfers turning effort from the engine to the driving wheels. It include a clutch ( manual transmission) or a torque converter (automatic transmission), a transmission drive shaft, final drive and differential gear s and driving axles. Alternatively, a transaxle may be used. A transaxle is a self-contained unit with a transmission, final drive gears and differential located in one casing. The directional motion of vehicle is controlled by a steering system. A basic steering system has 3 main parts: a steering box connected to the steering wheel, the linkage connecting the steering box to the wheel assembly at the front wheels and front suspension parts to let the wheel assemblies pivot. When the driver turns the steering wheel，a shaft from the steering column turns the steering gear. The steering gear moves tie-rods that connect to the front wheels. The tie-rods move the front wheels to turn the vehicle right or left.5 The braking system and wheels The purpose of the complete suspension system is to isolate the vehicle body from road shocks and vibrations, which will otherwise be transferred to the passengers and load. It must also keep the tires in contact with the road regardless of road surface. A basic suspension system consists of springs, axles, shock absorbers, arms, rods and ball joints.The tire provides a cushion between the vehicle and the road to reduce the transmission of road shocks. It also provides friction to allow the vehicle to perform its normal operations. Modern tires are manufactured from a range of materials. The rubber is mainly synthetic. Two types of tire construction are common: cross-ply and radial. Most passenger cars now use radial tires, and radials are replacing cross-ply tires on 4-wheel drives and heavy vehicles.6 The braking system Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes expanding against the inside of the drum. With disc brakes, a disc attached to the wheel hub is clenched between two brakepads. On light vehicles, both of these systems are hydraulically operated. The brake pedal operates a master cylinder. Hydraulic lines and hoses connect the master cylinder to brake cylinders at the wheels. Most modern light vehicles have either disc brakes on the front wheels and drum brakes on the rear or disc brakes on a11 4 wheels. Disc brakes require greater forces to operate them. A brake booster assists the driver by increasing the force applied to the master cylinder when the brake is operated.7 The electrical and electronic system The charging system provides electrical energy for all of the electrical components on the vehicle. A typical charging system includes: a battery, an alternator, a voltage regulator which is usually integral to the alternator, a charging warning or indicator light and wiring that complete the circuits. The battery provides electrical energy for starting, then once the engine is running the alternator powers all the electrical components of the vehicle. The alternator also charges the battery to replace the energy used to start the engine. The voltage regulator prevents overcharging. The starting system consists of the battery, starter, flywheel ring gear, cables，and the ignition switch. The starter motor is powered by the battery. During starting, the pinion of the starter motor engages with the flywheel ring gear and the starter motor then operates to crank the engine. El