suspention system

SUBMITTED TO SUBMITTED BY

Mr. AMIT SARAF MOHIT PUROHIT

(H.O.D. MECHANICAL ME 4th YEAR

DEPARTMENT) 13EBTME022

BHARTIYA INSTITUTE OF ENGINEERING AND TECHNOLOGY

SUMMER TRAININGat

TRIUMPH MOTORS : A Unit of Shriya Overseas Pvt. Ltd.

• History of CHEVROLET

• About TRIUMPH MOTORS

• Introduction to suspension system

• Functions of suspension system

• Requirements of suspension system

• Elements of suspension system

• Springs

• Dampers(or shock absorbers)

• Strut

● Louis Chevrolet and William C. Durant founded the

"Chevrolet Motor Car Company" in Detroit on

November 3, 1911.

● William C. Durant also founded General Motors in

1908.

● In 1912, first car “Classic Six,” a luxurious high-

performance

six-cylinder model, hit the streets of Detroit.

● General Motors India was established in 1928, in

Mumbai .

Chevrolet Classic Six Spark model 2013

Cruze model 2013 Spark model 2016

Department

Sale

Service

Accidental

Denting and

Painting

About TRIUMPH MOTORS

MANAGEMENT SYSTEM

GENRAL MANAGER

SERVICE MANAGER

SERVICE ADVISOR

FIOOR SUPERVISOR

TECHNICIAN

HELPER

WASHER

Introduction to suspension

system

● The suspension system of an automobile is one

which separates the wheel/axle Assembly from

the body.

● The primary function of the suspension system

is to isolate the vehicle structure from shocks

and

vibration due to irregularities of the road

surface.

Functions of suspension

system

To prevent the road shocks from being

transmitted to the vehicle frame.

To preserve the stability of the vehicle in

pitching or rolling.

To safeguard the occupants from road shocks.

To provide good road holding while driving,

cornering and braking.

Requirements of a suspension system

Low initial cost.

Minimum weight.

Minimum tyre wear.

Minimum deflection consistent with required

stability.

Assembly of suspension

system

Elements of suspension system

Springs are resilient

members and as such act

as reservoirs of energy .

I t store the energy due to

the sudden force which

comes when vehicle

encounters a bump or a

ditch .

They reduce the

tendency of the carriage

unit to continue to

“bounce” up and down on

its springs .

Oscillation due to road

shocks are restricted to a

reasonable level by

damper.

SPRING DAMPER

1. Leaf spring

2. Coil spring

3. Torsion bars

4. Air and gas

spring

5. Rubber spring

Property of Spring

Springs used for

suspension system

should absorb road

shocks quickly and

return to the original

position slowly.

1. Leaf Spring

● Leaf spring are multi-layered steel plates clamped together in reducing length.

● Each strip is called a leaf. They are joined together by clamps and a central bolt.

● The length of each leaf

decreases so that the spring assembly act as a flexible beam and is of uniform strength.

2. Coil Spring

● It is a section of Spring

steel rod wound in a spiral

pattern or shape.

● These coils cushion and absorb the shocks and

bumps as the vehicle is

driven.

● Often the Shock absorbers

run up the center of the coil

springs.

A torsion bar is a solid bar of steel which is

connected to the car chassis at one end, and

free to move at the other end.

The springing motion is provided by the metal

bar's resistance to twisting.

Torsion bars are normally locked to the

chassis and the suspension parts with splined

ends.

In these springs compressed air or

gases filled in the cylinder or bellows

against which the wheel movement is

transmitted through diaphragm. As

soon as the wheel passes over a road

irregularity the compressed air returns

the system to its original position.

4.1. Disadvantages of Air and Gas

Spring

1. High cost .

2. Risk of breakdown.

3. Freezing of moisture in air in cold

weather.

4. Greater maintenance required

Damper Working principle

● Hydraulic dampers are prevalent

● During bumps or compression, rod &

piston move into the Shock Absorber.

● In rebound, or extension, they move out

● For dampening to be effective,

resistance is needed in both directions –

provided by oil and valves

Hydraulic Damper

● Without a damper structure a car spring will extend and release the energy it absorbs from a bump at an uncontrolled rate.

● The spring will continue to bounce at its natural frequency until all of the energy originally put into it is used up.

● A suspension built on springs alone would make for an extremely bouncy ride and, depending on the terrain, an uncontrollable car

Mathematical Model

● Quarter car model with asymmetric

damping:

● Components:

a)Spring mass

b)Un-spring mass

m1=spring mass, m2=un-spring mass

k1=stiffness coefficient of suspension

k2=stiffness of tire

b1=damping coefficient of suspension

b2=damping co-efficient of tire

● Damping coefficient of tire is usually

negligible in comparison with that of

spring.

MacPherson strut

● Combines a shock

absorber and a coil

spring into a single

unit.

● Provides a more

compact and lighter

suspension system

used for front-wheel

drive vehicles.

Jobs perform by Strut

They provide a dampening function like shock

absorbers, and they provide structural support

for the vehicle suspension.

That means struts deliver a bit more than

shock absorbers, which don’t support vehicle

weight , they only control the speed at which

weight is transferred in a car, not the weight

itself.

References

Hydraulic shock absorbers.OTO-HUI.COM

https://www.youtube.com/watch?v=vcSH2z706rU&list=P

LD41CECBDA5664881&index=37

Chevrolet suspension system in 1938 - Ella73TV

https://www.youtube.com/watch?v=1W_J6UhQP6s

Use of nonlinear asymmetrical shock-absorber to

improve comfort on passenger vehicles

M. Silveira , B.R.PontesJr., J.M.Balthazar - Journal of

Sound and Vibration

http://www.carbibles.com/suspension_bible.html

Motor Vehicle Dynamics – Modeling and Simulation

– Giancarlo Genta 31