INTRODUCTION AUTOMOBILE ENGINEERING

ME14 606 - ME14 606 - AUTOMOBILE ENGINEERINGAUTOMOBILE ENGINEERINGModule -1 Module -1

Sukesh O.P.Sukesh O.P.

Asst. Professor - MEAsst. Professor - ME

Jyothi Engineering CollegeJyothi Engineering College

May 2, 2023 ME14 606 /SOP& ARA/APME/JECC 1

ME14 606 AE

Objectives•1 To develop understanding about various automobile components and systems•2 To impart concepts modern automotive controls and safety features


MODULE I – Course Plan


• Introduction – classification of automobiles- automobile terminology. Modern energy systems for automotive application -Electric vehicles – hybrid vehicles – LPG and CNG fueled vehicles – hydrogen fueled vehicles.(basics only)

• Chassis and body – body parts, functions, types, material and construction. Engines - component details and materials for cylinder head, cylinder block, piston, piston rings , connecting rod, crank shaft, valve actuating mechanism, VVT(Variable Valve Timing).

• Modern Fuel systems: Working and advantages of: Petrol injection – MPFI (Multi Point Fuel Injection), GDI (Gasoline Direct Injection), High pressure pump &Injectors, Diesel Injection- CRDI (Common Rail Direct Injection), Electronic Diesel Control (EDC).

What is an ‘Automobile’??

• A vehicle producing power within itself for its propulsion is known

as a Self propelled vehicle.

• Eg. Moped, Scooter, motorcycle, Car, jeep, truck, tractor, ships,

aircrafts, rocket etc.

• A self propelled vehicle used for transportation of goods &

passengers on the ground is called an Automobile.

• Different from Aeronautical vehicles (planes, helicopters, rockets) &

marine vehicles (ships, boats, submarines)


History of Automobiles

Captain Nicholas Joseph Cugnot – French Army – built the first self propelled vehicle in 1768-70


First Automobile

Cugnot Steam Trolley, Steam Engine powered, 1768May 2, 2023 ME14 606 /SOP& ARA/APME/JECC 6

Karl Benz

Inventor of the first gasoline powered automobile, 1886May 2, 2023 ME14 606 /SOP& ARA/APME/JECC 7

Benz Patent Motorwagen – 1886 – first production car powered by an IC Engine – 954 cc, 2/3 hp or 0.5 kW at 250 rpm



Flocken Elektrowagen – 1888 – World’s first electric carMay 2, 2023 ME14 606 /SOP& ARA/APME/JECC 10

Henry Ford, American Industrialist – Ford Motor Company – founder of the first affordable Motorcar


COMPONENTS OF AN COMPONENTS OF AN AUTOMOBILEAUTOMOBILE

1. The Basic structure

2. The Engine

3. The Transmission system

4. The Auxiliaries

5. The Controls

6. The Superstructure


COMPONENTS OF AN AUTOMOBILECOMPONENTS OF AN AUTOMOBILE

1.1. The Basic Structure: The Basic Structure:

It consists of the frame, the suspension system, axles, wheels

and tyres.

2.2. The Engine: The Engine:

It provides the motive power for all various functions which

the vehicle or any part of it, may be required to perform. The

engine for automotive use is IC type.


ENGINE



3. 3. The Transmission System:The Transmission System:

It consists of a Clutch, a gear box giving four, five or even

more different ratios of torque output to torque input, a

propeller shaft to transmit the torque output from the gear box

to the rear axle and a differential gear to distribute the final

torque equally between the driving wheels.


Transmission System



4. 4. The Auxiliaries:The Auxiliaries:

The Electrical systems.

5.5. The Controls: The Controls:

They consists of steering systems and brakes

6.6. The Super Structure: The Super Structure:

In those cases where frameless construction is not

adopted there must be super structure i.e, the body.


Engine SystemsEngine Systems

1. Cooling System

2. Fuel System

3. Lubrication System

4. Ignition System

5. Electrical System


Basic Engine Terminology1. Bore: The inside diameter of the cylinder is called bore2. Stroke: The linear distance along the cylinder axis between two

limiting position s is called stroke.3. Top Dead Center ( T.D.C.) : The top most position of the piston

towards cover end side of the cylinder is called T.D.C. 4. Bottom dead Center ( B.D.C.) : The lowest position of the piston

towards the crank end side of the cylinder is called B.D.C.5. Clearance Volume : The volume contained in the cylinder above

the top of the piston , when the piston is at top dead center , is called the clearance volume.

6. Swept Volume: The volume swept through by the piston in moving between T.D.C. and B.D.C, is called swept volume or piston displacement.

Basic Engine Terminology

7. Compression Ratio: It is the ratio of Total cylinder volume to clearance volumeComp. Ratio

6:1 to 10:1 for Petrol engines15:1 to 25:1 for Diesel engines

Comp. Temp.250*C for S.I.600*C for C.I.

Comp. Pressure1 MPa for S.I.3.5 MPa for C.I.

Classification Of Automobiles

1.1. Based on PurposeBased on Purpose1. Passenger Vehicles – Car, Bus, Motorcycle2. Goods Vehicles – Lorry, truck, Pick up

2.2. Based on CapacityBased on Capacity1. Heavy Motor Vehicle (HMV) – large trucks, Buses, Tractor2. Light Motor Vehicle (LMV) – Cars, Jeep, Motor cycles3. Medium Vehicle – Small trucks, Minibus, Tempo


Classification Of AutomobilesClassification Of Automobiles

3. Based on Fuel Source3. Based on Fuel Source1. Petrol Engine 2. Diesel Engine3. Gas Vehicles 4. Solar Vehicles5. Hydrogen Vehicles 6. Electric Vehicles7. Steam Engine vehicles8. Hybrid Vehicles9. Hybrid Electric Vehicles

4. 4. Based on Type of TransmissionBased on Type of Transmission1. Automatic transmission vehicles – mostly American2. Conventional transmission vehicles – Most Indian Vehicles3. Semi - Automatic transmission vehicles – mostly British



5. Based on Make5. Based on Make

1. MARUTI SUZUKI 2. HINDUSTAN MOTORS

3. TATA MOTORS 4. MAHINDRA & MAHINDRA

5. TVS MOTORS 6. HERO MOTOCORP

7. ASHOK LEYLAND8. EICHER MOTORS

9. FORCE MOTORS 10. BAJAJ AUTO LTD

11. ROYAL ENFIELD

12.VOLVO, VOLKSWAGEN, MERC BENZ, BMW,

CATERPILLAR, BENTLEY, AUDI etc.



6. With respect to the drive6. With respect to the drive1. Left Hand Drive 2. Right Hand Drive3. Fluid Drive 4. Front Wheel Drive5. Rear Wheel Drive 6. All Wheel Drive (AWD or 4WD)

7. 7. With respect to the SuspensionWith respect to the Suspension1. Conventional – Leaf Spring2. Independent – Coil, Torsion bar, MacPherson Strut



8. With respect to the Type of Engine8. With respect to the Type of Engine1. Reciprocating – Piston Engines2. Rotary – Wankel Engine, Gas turbine

9. With respect to the body & doors9. With respect to the body & doors1. Sedan 2. Hatchback3. Station Wagon4. Convertible5. Sports utility vehicle6. Multi Utility Vehicle (MUV or MPV)7. Delivery Vans etc



1010. Based on no. of wheels. Based on no. of wheels1. Two wheeler2. Three wheeler3. Four 4. Six


Indian Automakers


European Automakers


Japanese Automakers


American Automakers


Italian Automakers


French Automakers


Swedish Automakers


German Automakers


Rank of Manufacturer’s by production (2013)

1. TOYOTA – JAPAN 6. NISSAN – JAPAN

2. GENERAL MOTORS – USA 7. FIAT CHRYSLER – ITALY

3. VOLKSWAGEN – GERMANY 8. HONDA – JAPAN

4. HYUNDAI – SOUTH KOREA 9. SUZUKI – JAPAN

5. FORD – USA 10. RENAULT - FRANCE


This is a list of the 10 largest manufacturers by production in 2015Rank Group Country Vehicles

1 Toyota Japan 10,083,831

2 Volkswagen Germany 9,872,424

3 Hyundai South Korea 7,988,479

4 General Motors United States 7,485,587

5 Ford United States 6,396,369

6 Nissan Japan 5,170,074

7 Fiat Chrysler Automobiles Italy/ United States 4,865,233

8 Honda Japan 4,543,838

9 Suzuki Japan 3,034,081

10 Renault France 3,032,652


The Transmission systemThe Transmission system

General layout of transmission system of an automobileMay 2, 2023 ME14 606 /SOP& ARA/APME/JECC 37

Functions of transmission systemFunctions of transmission system

1. To disconnect the engine from the road wheels when required.

2. To connect the engine to the driving wheels without shock

3. To vary the leverage between the engine and driving wheels.

4. To reduce the engine speed permanently in a fixed ratio

5. To turn the drive through a right angle.

6. To make provision such that the driving wheels may rotate at

different speeds while taking turns.


Various components of transmission system

1) Engine

2) Clutch

3) Gearbox

4) Universal joints

5) Differential

6) Wheels

7) Front and rear axles


. ClutchClutch : Its purpose is to enable the driver to disconnect the

drive from the road wheels instantaneously and to engage

drive from the engine to the road wheels gradually while

moving the vehicle from rest.

GearboxGearbox : The gear box or the transmission provides the

necessary leverage variation between the engine and road

wheels.

DifferentialDifferential : While taking turns, the driving wheels must at

different speeds. This is done with the help of differential.


Engines



Engine & Engine componentsEngine & Engine components



Engine & Engine componentsEngine & Engine components1. Cylinder Block 2. Cylinder head3. Crankcase 4. piston5. Piston rings 6. Piston pin7. Connecting rod 8. Crank shaft9. Flywheel10. Valves and valves mechanism11. Rocker arm 12. Camshaft13. Accessories: Air cleaner, oil filter, automatic chokes,

automatic heat controls.other parts: Spark plug, ignition devices, carburetor


Engine componentsEngine components1.1. Cylinder blockCylinder block

It consists of three parts.

The cylinder in which the pistons slide up and down.

The passages for the flow of cooling water.

The bottom of the block supports the crankshaft, oil sump and

camshaft.

• Various engine accessories & clutch housing are bolted to it.

The Cylinder block is usually made from grey cast iron. Sometimes its

made with addition of nickel or chromium, Aluminium and Compacted

Graphite Iron(CGI) – heavy duty alloy.


Engine components : Engine components : 1.Cylinder block1.Cylinder block

Cylinder block and crankcase form a single casting

(monoblock). It gives a rigid structure and extra strength.

The Cylinder block may also have a separate crankcase for

the crankshaft.(Individual block)

Advantages of Monoblock

No water leakage, more rigid

Size is reduced, easy water circulation

Advantages of Individual block

Easy for repairing, less replacement cost


Cylinder Block (Monoblock)


2. Cylinder Head2. Cylinder HeadThe top of the cylinder is covered by a separate cast piece known as

the cylinder head. It is bolted to the cylinder block.

It is usually made of grey iron or Aluminium alloy. Aluminium has the

advantage of light in weight and high heat conductivity.

A flat piece of gasket is placed is placed between the cylinder head

and block to retain compression in the cylinder and to provide a gas and

water tight seal.

Gasket made of Copper-asbestos-Copper.•Camshafts, rockers & valves may be carried on the cylinder head.•Water passages may also be provided to cool the valves, the head and the spark plugs.May 2, 2023 ME14 606 /SOP& ARA/APME/JECC 49


3.Piston3.Piston

Piston helps to convert the chemical energy obtained by

the combustion of fuel into useful mechanical power.

The purpose of the piston is to provide a means of

conveying the expansion of the gases to the crankshaft through

the connecting rod.

It is provided with piston rings to provide a good seal

between the cylinder wall and piston. It has to withstand very

high temperatures of combustion.



PistonPiston

Materials Used

Aluminium alloys, Cast steel, Cast Iron or Chrome Nickel


Engine components :Engine components : PistonPiston

Head or Crown: top of the piston

Ring grooves

Skirt: parts below the ring grooves

Lands: the portion that separates the grooves.

The piston must posses the following qualitiesThe piston must posses the following qualities

Rigidity to withstand high pressure.

Lightness to reduce weight and inertial forces.

Good heat conductivity to reduce the risk of detonation

Silence in operation


4.Piston rings4.Piston rings

Fine grained alloy cast iron used for the piston rings.

Cast Iron plated with Chromium, Cadmium or Tin.

Functions:Functions:

Prevent the escape of burnt gases from the combustion chamber

past the piston (Crank case blow by).

Prevent the leakage of oil into the combustion space.

Heat from the piston is transmitted to the cylinder via piston

rings.


Piston Rings



a.a. Compression rings:Compression rings:o Prevents the blow by or escape of burnt gases to the crank case.

o 2 or 3 compression rings are fitted into the top grooves.

o A gap is formed in the ring to impart the property of radial

expansion and compression.

o This gap is necessary for assembly and renewal of ring

o Made from Cast Iron plated with Chromium, Cadmium and Tin.


Compression Ring



b. Oil Control rings:b. Oil Control rings:

oThese rings scrap off excessive oil from the cylinder wall and

return it to the oil sump.

oThe oil control ring is fitted into the lower groove of the piston.

oOil control grooves has a series of slots. These slots transfer the

excess oil through the holes in the piston groove to the inside of

the piston and to the sump

oMade from steel, outer edges of the rings chromium plated



5.Connecting rod5.Connecting rodThe connecting rod usually has I-beam cross-section.

Small end is connected to the piston pin and big end to the crank pin

The function of the connecting rod is to convert linear motion of the

piston into rotary motion of the crankshaft.

The connecting rod carries the power thrust from piston to the crank

pin. So it must be strong, rigid and as light as possible.

Always made from steel forgings, in few cases Aluminium alloy is

used.


5. Connecting rod5. Connecting rod

• Cross section is an “H” or “I”

• Types include :

a) Plain Rod

b) Fork and blade rod

c) Master and articulated


a) Plain Roda) Plain Rod

o Used on inline and opposed engines

o Small bushing at piston pin end is pressed in place and reamed to

final dimensions

o Large end of rod includes a cap, bolts, nuts, and plain bearing

inserts

o Rods are numbered as to cylinder and for cap-to-rod alignmentMay 2, 2023 ME14 606 /SOP& ARA/APME/JECC 63

b) Fork and Blade Connecting Rodb) Fork and Blade Connecting Rod

• Used on “V” type engines

• One rod inside another allows cylinders to be aligned and to

share a common location on the crankshaft


Fork and Blade Type C Rod


c) Master and Articulating Rodc) Master and Articulating Rod

o Used on radial engines

o Uses “knuckle pins” to retain articulated rods to master


6. Crank shaft6. Crank shaft

It is the 1st part in the power transmission.The reciprocating motion of the piston is converted into rotary motion of the crankshaft with the help of connecting rod.It consists of crankpins, webs, balancing weights and main journals. Big end of connecting rod is connected to the crankpin of the crankshaft.The crank shaft is supported by the main bearings on the main journals.Made of Casting or forging of heat treated alloy steel.


Crankshaft


Engine components :Engine components : 6.Crank shaft6.Crank shaft


Valve Actuating MechanismsValve Actuating Mechanisms To admit the air-fuel mixture in the engine cylinder and to force

the exhaust gases out at correct timings, some control system is

necessary, which is provided by the valves.

The engine valves may be broadly divided into 3 main categories:

1. Poppet valve

2. Sleeve valve

3. Rotary valve

A most common type of valve used at present is poppet valve.


Valves

• Usually made of Austenitic Stainless Steel which is a corrosion &

heat resisting material.

• Race engines use Beryllium-Copper alloy seats with Titanium

valves (21-4N) – 40% lighter than Steel.



Poppet ValvePoppet Valve

• The valves are operated by cams mounted on a camshaft.

• According to the location of the valves,

the valve mechanisms are

a. Straight poppet valve mechanism

b. Overhead poppet valve mechanism

c. Overhead camshaft mechanism


.

• The valve mechanism to operate

the valve when it is in the

engine block(as in L,T and F-

head).

a. Straight (or side) poppet valve a. Straight (or side) poppet valve mechanismmechanism



b. Overhead poppet valve mechanismb. Overhead poppet valve mechanism

• The valve mechanism to operate the

valve when it is in the cylinder head( as in

I and F head design).

• It requires two additional moving parts-

the push rod and the rocker arm. As the

cam rotates, it lifts the valve tappet.

• It actuates the push rod and thereby the

rocker arm end pushes the valve stem to

open the valve.

c


Overhead Poppet Valve Mechanism



c. Overhead camshaft mechanismc. Overhead camshaft mechanism• In this type, the camshaft is mounted

above the valve in the cylinder head.

• The cam on the cam shaft operates

the valve directly. A small

clearance is provided in between the

cam and valve cap.

• The clearance is adjusted by

providing small shims in the bottom

of the cap.

c



SOHC & DOHC



Variable Valve Timing (VVT)


Variable Valve Timing (VVT)

• Variable Valve Timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with variable valve lift systems.


• 1. Phase changing systems: 1. Phase changing systems: With a single camshaft, all the valve events for both intake and exhaust valves are shifted by the same amount, whereas if separate camshafts are used for intake and exhaust valves, such a phase changing system can change the valves events can be changed independently for the intake and the exhaust valves.


2. Profile switching systems:2. Profile switching systems: these can change independently the valve-event timing and the valve lift. There are two camshafts with separate cam profiles. The system enables the valve operation to be switched between these camshafts at a particular engine speed.-High power output-Low emission level


3. Variable event-timing systems:3. Variable event-timing systems: can change both the phase and duration of valve events and can be optimized for different engines speed and load conditions due to which it is obtain:I.Increase in full-load torque.II.Reduction in part-load emissions.III.Fuel economy e.g. decrease of exhaust emissions.


4. Variable lift systems: 4. Variable lift systems: the main adv. Of such systems is reducing the pumping losses due to convectional throttle. 5. Electronic valve actuation systems: 5. Electronic valve actuation systems: due to their precise control, these have the maximum potential for optimizing the valve events. Besides, all the valve events including the lift csn be directly controlled.


Automobile Chassis

• Chassis – French term used to denote the main structure of a vehicle

• It’s the backbone of the vehicle – made of steel.

• All moving parts are fitted to it.

• To give it extra strength it is provided with bolted, riveted or welded

cross pieces.

• All major units required to propel the vehicle, direct its motion,

stop it as well as permit to run smoothly over varying road surface

is known as chassis.


Automobile Chassis

• The power unit is connected with the transmission.

• The structural frame fitted to the axles through the suspension

system carries the power train.

• For an automobile to propel safely on the road, the engine, the

transmission system, suspension, steering & brakes are included to

the basic frame. These units combined together – Chassis.

• The body or Cabin is jointed to the cabin by means of bolts & nuts

or by welding.



Chassis Components

• Frame• Front Suspension• Steering Mechanism• Wheels, Tyres and axles – rear & front springs & shock absorbers• Engine, Clutch & Gearbox• Propeller shaft• Radiator• Differential, half shaft & universal joint• Brakes & Braking system• Fuel tanks, pipes & connecting fuel lines.• Battery & electrical system• Silencer• Car Body• Car Body accessories like lights, radio, wiper, mirrors etc.


• Fast pick up• Strength & Safety• Durability• Dependability• Ease of control• Quietness• Speed• Power accessibility• Low centre of gravity• Simplicity of lubrication• Economy of operation.

Desired qualities of a Chassis


body

