08-01-2013, 11:37 AM
Introduction to Automobile
Introduction to Automobile.ppt (Size: 1.82 MB / Downloads: 146)
Components of an Automobile
The basic structure
The power unit
The transmission system
The auxiliaries
The controls
The superstructure
The Basic Structure (Chassis)
This is the unit on which the other units are mounted.
It consists of:-
Frame
The Suspension system
Axles
Wheels
Tyres
Frame
There consists of two distinct forms construction in common use:
The conventional pressed steel frame to which all units are mounted
The integral or frameless construction, in which the body structure is so designed so as to combine the functions of body and frame.
Frameless - Advantages
Reduced weight and consequent saving in fuel consumption
Lower manufacturing costs
Safety to passengers
Increased stability of the automobile
Disadvantages
Reduction in strength and durability
Economical only if it is adopted in mass production
Increased cost or repairs
Convertible cars are difficult to design in frameless construction
Suspension System
The objects of the suspension are:
To prevent the road shocks from being transmitted to the vehicle components
To safeguard the occupants from road shocks
To preserve the stability of the vehicle while in motion
Axles
It is the wait carrying members, may be on the rear or front, are beams supported at ends.
Axles are subjects to different kin of loads:
Vertical load due to self weight
A fore and aft load due to driving and braking
Torque reactions due to drive and brake
Side thrust due to centrifugal force during conference
Front engine FWD
The power is transmitted to front axles, from the front engine (Front Wheel Drive)
A few advantages are:
The propeller shaft is eliminated. This permits low chassis height
The pulls the car than pushing it, avoiding skidding tendency.
Better road adhesion.
Front engine four wheel drive
Vehicles which operate on rough roads and unexpected road profiles, all the four wheels are the driving wheels
It has got an extra transfer box, which divides the torque between front and rear wheels.
Also there is a provision for disengaging the front wheels when not required.