CH03 automotive systems STUDENT VERSION rev

Tài liệu học tập cơ bản khái quát về động cơ và các bộ phận trên ô tô phiên bản tiếng anh. Tài liệu này nhằm giúp chúng ta tiếp cận được cấu tạo chức năng của các bộ phận của xe. Với tài liệu này giúp các bạn sinh viên ngành cơ khí ô tô tiếp cận được những kiến thức cơ bản về ô tô và đồng thời nâng cao kiến thức tiếng anh. Bộ tài liệu này được soạn thảo bởi trường đào tạo và huấn luyện nghề ở Canada.

Chapter 3

Automotive Systems

Automotive History

• Early vehicles were powered by electricity or steam

• Most bodies were open carriage designs

• Few major changes from the 1930s until the 1960s

• Improved safety and pollution controls in the 1960s

• OPEC oil embargo created fuel shortages and the demand for smaller, more efficient vehicles

• The Corporate Average Fuel Economy (CAFE) standard set in 1975

• Leaded fuel phased out

• Catalytic converters introduced

• Mechanical systems replaced by electronic

components

• First use of electronic engine controls

• Anti-Lock brakes introduced

• Passive restraint systems and air bags installed

• Fuel injection replacing carburetion

• Fuel injection standard on all engines

• Increasing use of electronics and computers

• Passive restraints and ABS standard equipment on new cars

• First hybrid vehicles appear

• Electronics and computer systems manage most on-board vehicle functions

• GPS, navigation, adaptive cruise control, and dynamic vehicle control systems standard

equipment

• Hybrids available from several manufacturers

Typical Body Over Frame

A Unibody Design

The Basic Engine

• Gasoline engines most

common in passenger

cars

• Uses a spark ignition

system

• Combined with

electric motors in

hybrid vehicles

• Diesel engines most common in heavy duty applications

• Uses compression pressure for ignition

• Newer diesels much cleaner and quieter

Cylinder Block

• Made from cast iron or

aluminum

• Contains the

crankshaft, pistons,

and connecting rods

• Forms the lower half

of the engine

Cylinder Head

• Mounts on top of

engine block

• Made of cast iron or

aluminum

• Contains camshaft and

valves

• Has intake and exhaust

manifolds attached

Engine Systems

• Lubrication system

• Cooling system

• Fuel and air system

• Emission control

system

• Exhaust system

• Ignition system

• Starting and charging system

• Electronic engine control system

• On-board diagnostics

Lubrication System

• Supplies clean oil to

various parts of the

engine

• Removes heat from

combustion

• Removes combustion

by-products

• Filters oil

Cooling System

• Removes heat from

combustion

• Maintains proper

engine operating

temperature

• Supplies heat for

passenger

compartment

Fuel and Air Systems

• Fuel system stores and

supplies fuel to the

engine

• Contains fuel tank,

pump, and filter

• Fuel is injected into

engine by fuel

injectors

• Air intake system supplies filtered air to the engine

• Air is drawn into the cylinder and mixed with fuel for

combustion

Ignition System

• Must ignite the air/fuel mixture a precisely the

correct time

• Boosts battery voltage to 20,000 – 40,000 volts

• Changes spark timing based on engine load, speed, and other factors

Starting and Charging Systems

• Electric motor converts stored energy into motion

• Generator converts movement into electrical

energy

• Starter motors and generators can be conventional 12v or part of hybrid motor/generator assembly

Heating System

• Uses coolant heated by the

engine to warm the

passenger compartment

• Thermostat maintains

minimum system

temperature

Air Conditioning

• The A/C system removes

heat and moisture from the

passenger compartment

• The A/C compressor can be

belt driven or electric on a

hybrid vehicle

Hybrid Electric Vehicles (HEVs)

• HEVs use one or more electric motors and an

internal combustion engine (ICE) to propel the

vehicle

• HEVs recapture braking energy to recharge the

high-voltage batteries

• The high-voltage batteries pose a significant safety hazard if proper precautions are not followed