basics about automobile chassis, frame and body.

1. To study automobile
chassis and automobile
body
Prepared by : Rudrik Joshi

2. Chassis
 Chassis is a French term and was initially
used to denote the frame or main
structure of a vehicle.
 The term chassis is now extensively used
to denote the complete vehicle except
body for the heavy vehicle a separate
body.

3. Components of chassis
 Chassis contains following components:
1. Frame
2. Front axle
3. Rear axle
4. Steering system
5. Suspension system
6. Engine
7. Brake system

4. Classification of chassis
 According to its control
1. Conventional chassis
2. Semi forward chassis
3. Full forward chassis
 According to fitting of engine:
1. Engine at front
2. Engine fitted in front but crosswise
3. Engine fitted at centre of chassis
4. Engine fitted at back

5. Cont.
 According to number of wheels fitted in vehicle and the number of driving
wheel:
1. 4 * 2 drive chassis vehicle
2. 4 * 4 drive chassis vehicle
3. 6 * 2 drive chassis vehicle
4. 6 * 4 drive chassis vehicle

6. Frame
 The frame is the main part of chassis on
which the remaining parts of the chassis
are mounted.
 It is a rigid structure that forms a skelton
to hold all the major parts together.
 The engine is mounted on forward end of
frame.

7. Function of frame
 The main function of frame are :
1. To support the chassis components and the body.
2. To withstand static and dynamic loads with undue deflection.

8. Types of frame
 The frames are made of following steel sections:
1. Channel section: for long member, good in bending
2. Box section : for short member, good in bending and torsion
3. Tubular section : good in torsion

9. Cont.
1. Conventional frame:
 It is also known as non load carrying frame. Here the load on vehicles are
transferred to the suspension by frame.
 The body is made of wood.
 Not much suited to resist torsion.
2. Semi integral frame:
 Rubber body mounts are replaced by relatively stiff mounts so that a part of
frame load is transferred to body structure.
 This frame is heavy.

10. Cont.
3. Integral frame:
 In this type there is no frame and all assembly are attached to the body.
 In this, the chassis becomes a sub frame and other sub frames are used for
the front and rear suspnsion units.

11. Body
 Body is the super structure of vehicle.
 The chassis and body makes the complete
vehicle.
 In larger vehicles, the chassis and body are
each made as a separate unit and then
bolted together.
 The body is usually made from a large
number of steel pressing which are welded
together.

12. Types of body