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Advanced Vehicle Technology To my long-suffering wife, who has provided sup- port and understanding throughout the preparation of this book. Advanced Vehicle Technology Second edition Heinz Heisler MSc., BSc., F.I.M.I., M.S.O.E., M.I.R.T.E., M.C.I.T., M.I.L.T. Formerly Principal Lecturer and Head of Transport Studies, College of North West London, Willesden Centre, London, UK OXFORD AMSTERDAM BOSTON LONDON NEW YORK PARIS SAN DIEGO SAN FRANCISCO SINGAPORE SYDNEY TOKYO Butterworth-Heinemann An imprint of Elsevier Science Linacre House, Jordan Hill, Oxford OX2 8DP 225 Wildwood Avenue, Woburn, MA 01801-2041 First published by Edward Arnold 1989 Reprinted by Reed Educational and Professional Publishing Ltd 2001 Second edition 2002 Copyright # 1989, 2002 Heinz Heisler. All rights reserved The right of Heinz Heisler to be identified as the author of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988 No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a license issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1T 4LP. Applications for the copyright holder's written permission to reproduce any part of this publication should be addressed to the publishers Whilst the advice and information in this book are believed to be true and accurate at the date of going to press, neither the authors nor the publisher can accept any legal responsibility or liability for any errors or omissions that may be made. Library of Congress Cataloguing in Publication Data A catalogue record for this book is available from the Library of Congress ISBN 0 7506 5131 8 For information on all Butterworth-Heinemann publications visit our website at www.bh.com Typeset by Integra Software Services Pvt. Ltd, Pondicherry, India www.integra-india.com Printed and bound in Great Britain 1 Vehicle structure 1.1 Integral body construction 1.2 Engine, transmission and body structures 1.3 Fifth wheel coupling assembly 1.4 Trailer and caravan drawbar couplings 1.5 Semi-trailer landing gear 1.6 Automatic chassis lubrication system 2 Friction clutch 2.1 Clutch fundamentals 2.2 Angular driven plate cushioning and torsional damping 2.3 Clutch friction materials 2.4 Clutch drive and driven member inspection 2.5 Clutch misalignment 2.6 Pull type diaphragm clutch 2.7 Multiplate diaphragm type clutch 2.8 Lipe rollway twin driven plate clutch 2.9 Spicer twin driven plate angle spring pull type clutch 2.10 Clutch (upshift) brake 2.11 Multiplate hydraulically operated automatic transmission clutches 2.12 Semicentrifugal clutch 2.13 Fully automatic centrifugal clutch 2.14 Clutch pedal actuating mechanisms 2.15 Composite flywheel and integral single plate diaphragm clutch 3 Manual gearboxes and overdrives 3.1 The necessity for a gearbox 3.2 Five speed and reverse synchromesh gearboxes 3.3 Gear synchronization and engagement 3.4 Remote controlled gear selection and engagement m 3.5 Splitter and range change gearboxes 3.6 Transfer box power take-off 3.7 Overdrive considerations 3.8 Setting gear ratios 4 Hydrokinetic fluid couplings and torque converters 4.1 Hydrokinetic fluid couplings 4.2 Hydrokinetic fluid coupling efficiency and torque capacity 4.3 Fluid friction coupling 4.4 Hydrokinetic three element torque converter 4.5 Torque converter performance terminology 4.6 Overrun clutches 4.7 Three stage hydrokinetic converter 4.8 Polyphase hydrokinetic torque converter 4.9 Torque converter with lock-up and gear change friction clutches 5 Semi- and fully automatic transmission 5.1 Automatic transmission consideration 5.2 Four speed and reverse longitudinally mounted automatic transmission mechanical power flow 5.3 The fundamentals of a hydraulic control system 5.4 Basic principle of a hydraulically controlled gearshift 5.5 Basic four speed hydraulic control system 5.6 Three speed and reverse transaxle automatic transmission mechanical power flow 5.7 Hydraulic gear selection control components 5.8 Hydraulic gear selection control operation 5.9 The continuously variable belt and pulley transmission 5.10 Five speed automatic transmission with electronic-hydraulic control 5.11 Semi-automatic (manual gear change two pedal control) transmission system 6 Transmission bearings and constant velocity joints 6.1 Rolling contact bearings 6.2 The need for constant velocity joints 7 Final drive transmission 7.1 Crownwheel and pinion axle adjustments 7.2 Differential locks 7.3 Skid reducing differentials 7.4 Double reduction axles 7.5 Two speed axles 7.6 The third (central) differential 7.7 Four wheel drive arrangements 7.8 Electro-hydralic limited slip differential 7.9 Tyre grip when braking and accelerating with good and poor road surfaces 7.10 Traction control system 8 Tyres 8.1 Tractive and braking properties of tyres 8.2 Tyre materials 8.3 Tyre tread design 8.4 Cornering properties of tyres 8.5 Vehicle steady state directional stability 8.6 Tyre marking identification 8.7 Wheel balancing 9 Steering 9.1 Steering gearbox fundamental design 9.2 The need for power assisted steering 9.3 Steering linkage ball and socket joints 9.4 Steering geometry and wheel alignment 9.5 Variable-ratio rack and pinion 9.6 Speed sensitive rack and pinion power assisted steering 9.7 Rack and pinion electric power assisted steering 10 Suspension 10.1 Suspension geometry 10.2 Suspension roll centres 10.3 Body roll stability analysis 10.4 Anti-roll bars and roll stiffness 10.5 rubber spring bump or limiting stops 10.6 Axle location 10.7 Rear suspension arrangements 10.8 Suspension design consideration 10.9 Hydrogen suspension 10.10 Hydropneumatic automatic height correction suspension 10.11 Commercial vehicle axle beam location 10.12 Variable rate leaf suspension springs 10.13 Tandem and tri-axle bogies 10.14 Rubber spring suspension 10.15 Air suspensions for commercial vehicles 10.16 Lift axle tandem or tri-axle suspension 10.17 Active suspension 10.18 Electronic controlled pneumatic (air) suspension for on and off road use 11 Brake system 11.1 Braking fun 11.2 Brake shoe and pad fundamentals 11.3 Brake shoe expanders and adjusters 11.4 Disc brake pad support arrangements 11.5 Dual- or split-line braking systems 11.6 Apportional braking 11.7 Antilocking brake system (ABS) 11.8 Brake servos 11.9 Pneumatic operated disk brakes (for trucks and trailers) 12 Air operated power brake equipment and vehicle retarders 12.1 Introductions to air powered brakes 12.2 Air operated power brake systems 12.3 Air operated power brake equipment 12.4 Vehicle retarders 12.5 Electronic-pneumatic brakes 13 Vehicle refrigeration 13.1 Refrigeration terms 13.2 Principles of a vapour-compression cycle refrigeration system 13.3 Refrigeration system components 13.4 Vapour-compression cycle refrigeration system with reverse cycle defrosting 14 Vehicle body aerodynamics 14.1 Viscous air flow fundamentals 14.2 Aerodynamic drag 14.3 Aerodynamic lift 14.4 Car body drag reduction 14.5 Aerodynamic lift control 14.6 Afterbody drag 14.7 Commercial vehicle aeordynamic fundamentals 14.8 Commercial vehicle drag reducing devices Index 1 Vehicle Structure 1.1 Integral body construction The integral or unitary body structure of a car can be considered to be made in the form of three box compartments; the middle and largest compart- ment stretching between the front and rear road wheel axles provides the passenger space, the extended front box built over and ahead of the front road wheels enclosing the engine and transmission units and the rear box behind the back axle providing boot space for luggage. These box compartments are constructed in the form of a framework of ties (tensile) and struts (compressive), pieces (Fig. 1.1(a & b)) made from rolled sheet steel pressed into various shapes such as rectangular, triangular, trapezium, top-hat or a combination of these to form closed box thin gauge sections. These sections are designed to resist direct tensile and compressive or bending and torsional loads, depending upon the positioning of the mem- bers within the structure. Fig. 1.1 (a and b) Structural tensile and compressive loading of car body 1 [...]... sound generation and its dissipation 10 collision, but overall alignment may also be necessary if the vehicle' s steering and ride characteristics do not respond to the expected standard of a similar vehicle when being driven Structural misalignment may be caused by all sorts of reasons, for example, if the vehicle has been continuously driven over rough ground at high speed, hitting an obstacle in the road,... a glancing blow from some other vehicle or obstacle etc Suspicion that something is wrong with the body or chassis alignment is focused if there is excessively uneven or high tyre wear, the vehicle tends to wander or pull over to one side and yet the track and suspension geometry appears to be correct Alignment checks should be made on a level, clear floor with the vehicle' s tyres correctly inflated... points This is repeated from the other side At the points where these two arcs intersect a straight line is made with a plucked, chalked cord running down the middle of the vehicle This procedure should be followed at each end of the vehicle as shown in Fig 1.9 Once all the reference points and transverse and diagonal joining lines have been drawn on the Fig 1.8 Collision body safety which depends upon... crumble zones with very little impact energy actually being dissipated by the central body cell 1.1.6 Body and chassis alignment checks (Fig 1.9) Body and chassis alignment checks will be necessary if the vehicle has been involved in a major Table 1.1 Summary of function and application of soundproofing materials Function Acoustic materials Application Insulation Loaded PVC, bitumen, with or without foam... particularly in low gear, which would cause excessive misalignment and strain on such components as the exhaust pipe and silencer system 8 To restrict engine movement in the fore and aft direction of the vehicle due to the inertia of the engine acting in opposition to the accelerating and braking forces 1.2.3 Rubber flexible mountings (Figs 1.10, 1.11 and 1.12) A rectangular block bonded between two metal... flexibility in the horizontal longitudinal, horizontal lateral and vertical axis of rotation At the same time they must have sufficient stiffness to provide stability under shock loads which may come from the vehicle travelling over rough roads Rubber sprung mountings suitably positioned fulfil the following functions: Double inclined wedge mounting (Fig 1.18(b)) The inclined wedge angle pushes the bonded rubber . Advanced Vehicle Technology To my long-suffering wife, who has provided sup- port and understanding throughout the preparation of this book. Advanced Vehicle. Afterbody drag 14.7 Commercial vehicle aeordynamic fundamentals 14.8 Commercial vehicle drag reducing devices Index 1 Vehicle Structure 1.1 Integral