Chassis,Frame and Body construction notes PDF/ PPT

This post covers the construction of chassis, frame and body of the vehicle which is the one of the contents of vehicle structure and engines of the subject Automobile Engineering.

Chassis

Click: Types of frame construction

Ø      To construct any automobile, chassis is the basic requirement.

Ø        French term

Ø        A vehicle without body is called “chassis”. (A carrying unit)

Ø       Back bone of the vehicle

Ø       The components of the vehicle such as power plant, transmission system, axles, wheels and tyres,  suspension, controlling systems such as braking, steering etc.,

Ø  Electrical system parts are mounted on the chassis frame.

Ø       It is the main mounting of all components including the body. So it is called “carrying unit.”

Main components of chassis

  ž  Frame

        ž  Front suspension

ž  Steering mechanism

ž  Engine, clutch and gearbox

ž  Radiator

ž  Propeller shaft

ž  Wheels

ž  Rear and front springs & Shock absorbers

ž  Differential unit

ž  Universal joint

ž  Braking systems

ž  Storage battery

ž  Fuel tank

ž  Electrical systems

ž  Silencer 

žCharacteristics of good Chassis

 Fast pickup

ž   Strength

ž  Safety

ž  Durability

ž  Dependability

ž  Ease of control

ž  Quietness

ž  Speed

ž  Power accessibility

ž  Economy of operation

ž  Low centre of gravity

ž  Stability

ž  Load clearance

ž  Braking ability

ž  Good springing

ž  Simplicity of lubrication 

 Layout of Chassis

ž                    ž  In this layout, the engine location is at the front end of the vehicle.

      The drive of the engine can be connected or disconnected fro the gear box by using clutch assembly.

 ž         The clutch pedal provided at the vicinity of the driver             facilitates to engage or disengage the clutch with gearbox whenever required.

 From gearbox, power is transmitted to the differential through a propeller shaft and universal joints and finally to the wheels via rear axles.

ž  The radiator is placed at the front side of an engine. 

Components and drive systems in chassis

Frame:

Ø                  Frame is the foundation for carrying the engine and body of the vehicle.

Ø                  The frames are made of box, tubular, channel or U-shaped section, welded or riveted together. 

Click video:Chassis frame construction 

Suspension system

Ø  To insulate the wheel and axles from the frame in order to avoid the transmission of road effects to passengers while travelling on uneven road.

Ø    To provide comfortable ride to passengers.

Ø    To avoid additional stresses in the motor car frame.

  Steering System

Ø       Enable the driver to accurately control the direction taken by the vehicle under all operating conditions.

Ø        The system must be light and easy to operate, free from shock and vibration as direct as possible.

Ø       The steering system also helps to convert the rotary motion of the driver’s steering wheel into the angular turning of the front wheels as well as to multiply the driver’s effort with the leverage or mechanical advantage of turning wheels.

 Braking system

Ø  A brake is a mechanical friction device that inhibits motion, slowing or stopping a moving object (vehicle) or preventing its motion.

Ø  The most vital factor in running and controlling the modern vehicle.

Ø  Most brakes commonly use friction between two surfaces which can be pressed together to convert the kinetic energy of the moving vehicle into heat.

Click: Types of frame construction