AUTOMOTIVE CHASSIS AND COMPONENTS

Introduction

Types of chassis layout with reference to power plant locations and drive, Vehicle frames. Load acting on vehicle frame due to different systems.

Front Axle & Steering System

Types of front axles. Constructional details. Materials. Front wheel geometry viz. Castor, Camber, King pin inclination, Toe. Wheel Alignment. Cornering force and Side thrust. Steering geometry. Ackerman and Davis steering system. Different types of steering gear boxes. Steering linkages and their layouts. Power and power assisted steering. Steering of crawler tractors. Multi axle steering systems.

Driveline and Differential

Effects of driving thrust and torque reactions. Hotch kiss drive, torque tube drive and radius rods. Transverse rods. Propeller shaft. Universal joints. Constant velocity universal joints. Drive Shaft. Front wheel drive. Different types of final drives. Spiral bevel gear and hypoid gear final drives. Double reduction and twin speed final drives. Differential principles. Constructional details of a differential gear unit. Non-slip and Limited slip differential. Differential locks - Differential housings. Comparison of front wheel, rear wheel and all wheel drive arrangement.

Drive axles

Construction of rear axles. Types of loads acting on rear axles. Fully floating, three quarter floating, and semi floating rear axles. Rear axle housing. Construction of different types of axle housing, multi axled vehicles. Construction details of multi drive axle vehicles. Dead axles.

Suspension system

Need of suspension system, Types of suspension, Suspension springs, Constructional details and characteristics of leaf, coil and torsion bar springs, Independent suspension, Types: Mc Pherson strut, Double wishbone, Five link type, etc, Rubber suspension, Pneumatic suspension, Shock absorbers.

Wheels and Tyres

Types of wheels – wire spoke, disc – solid and split type, alloy type, offset, onset & zero set, denomination of rim. Tyres - construction, structure, denomination and function of tyres, types of tyres, comparison of radial and bias ply tyres. Tubes – construction and types, Tubeless tyres. Tyre inflation, effects of tyre pressure on tyre performance. Tyre wear patterns and their causes. Wheel Balancing – need, procedure.

Braking system

Weight transfer during braking and stopping distances. Classification of brakes - drum brakes and disc brakes. Constructional details. Theory of braking. Brake split and proportioning. Mechanical, hydraulic and pneumatic brakes - Servo brake, power and power-assisted brakes - Different types of brake retarders like eddy current and hydraulic retarder. Skidding of wheels on braking and remedies - Anti lock braking systems.