1、SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.Copyright 2002 Society of Automotive Engineers, Inc.All rights reserved. No part of this
3、 publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying,recording, or otherwise, without the prior written permission of SAE.TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (o
4、utside USA)Fax: 724-776-0790Email: custsvcsae.orgSAE WEB ADDRESS: http:/www.sae.orgSURFACEVEHICLE400 Commonwealth Drive, Warrendale, PA 15096-0001INFORMATIONREPORTJ2408REAF.JUL2002Issued 1997-10Reaffirmed 2002-07Superseding J2408 OCT1997Clutch Requirements for High-Torque Truck and Bus EnginesForewo
5、rdRecent technological developments in diesel engine design have made higher torque output and loweroperating speed engines readily available. As these engines push driveline components to their practical limit, ithas become necessary to formulate a “Next Generation” clutch installation system to ha
6、ndle higher levels ofoutput torque. While relating component torque capacity to design configuration is beyond the scope of SAERecommended Practices, it is to be noted that the current truck and bus clutch heavy-duty clutch standards areconsidered to provide torque capacity to about 2850 Nm (2100 lb
7、-ft) and the “Next Generation” clutch installationsystem is expected to provide torque capacity to about 4200 Nm (3100 lb-ft).TABLE OF CONTENTS1. Scope . 21.1 Purpose. . 22. References . 22.1 Applicable Publications 23. Definitions. 24. Technical Requirements. 24.1 Known Requirements . 34.1.1 Engine
8、 Flywheel Housing Size. 34.1.2 Pilot Bearing Requirements 34.1.3 Transmission Input Shaft Size. .34.2 Requirements Under Current Study. 34.2.1 Flywheel Size .34.2.2 Clutch Size . 34.2.3 Clutch Damper Requirements 34.2.4 Release Bearing Size. 34.2.5 Release Yoke Size and Placement 34.2.6 Clutch Brake
9、 Size and Splined Attachment 34.2.7 Clutch Housing Length. 34.2.8 Transmission Clutch Brake Surface . 3Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE J2408 Reaffirmed JUL2002-2-1. ScopeAlthough no
10、t limited to, these clutch requirements are normally used on trucks considered as HeavyDuty (Class 8).1.1 PurposeThis SAE Information Report defines and discusses clutch and related component configurationswhich will become the subject of future SAE Recommended Practices to promote standardization o
11、f clutchinstallations and mounting dimensions for use with pull-type heavy-duty clutches.2. References2.1 Applicable PublicationsThe following publications form a part of the specification to the extent specifiedherein. Unless otherwise indicated, the latest issue of SAE publications shall apply.The
12、 following publications define the existing clutch system design configuration which may need revision todefine the “Next Generation” clutch installation system for higher torque engines:2.1.1 SAE PUBLICATIONSAvailable from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.SAE J373Housing Inter
13、nal Dimensions for Single- and Two-Plate Spring-Loaded ClutchesSAE J617Engine Flywheel Housing and Mating Transmission Housing FlangesSAE J1463Pull-Type Clutch-Transmission Installation DimensionsSAE J1479Automotive Pull Type Clutch TerminologySAE J1731Pilot Bearings for Truck and Bus ApplicationsSA
14、E J1806Clutch Dimensions for Truck and Bus ApplicationsSAE J1857Flywheel Dimensions for Truck and Bus Applications2.1.2 TMC PUBLICATIONSAvailable from The Maintenance Council, American Trucking Associations, 2200 MillRoad, Alexandria, VA 22314.TMC RP 633 (T)Effects of Drivetrain Torsionals3. Definit
15、ionsThe following specific terms as used in this document are defined as follows:3.1 Heavy-Duty (Class 8) TrucksA truck or tractor rated by the manufacturer and certified to the US federalgovernment to be for operation at a gross vehicle weight or a gross combination weight of 14969kg(33001lbs) and
16、over.3.2 Next Generation Clutch Installation SystemThe engine, clutch, transmission, and clutch-release systemdesign parameters of the type defined in the referent documents which interface with the primary powertrainclutch as redefined to allow operation at engine output torque levels beyond the ca
17、pability of the existingcomponent designs.3.3 Soft Spring RateA clutch-disc spring rate designed to have a low-torsional spring rate, internal damping,and long-torsional travel in order to avoid normal vehicle operation at or near the vehicles drivetrain torsionalresonance frequency. See TMC RP 633
18、(T).4. Technical RequirementsThe SAE Truck and Bus Clutch Subcommittee and the SAE Truck and BusTransmission Subcommittee in a joint meeting have identified the design parameters for the “Next Generation”clutch which will need to be revised to define the package size requirements for clutches which
19、can handle thenext higher level of torque. Some of these parameters are known and some are currently under developmentas follows:Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE J2408 Reaffirmed JUL
20、2002-3-4.1 Known RequirementsDesign parameters considered fixed are as follows:4.1.1 ENGINE FLYWHEEL HOUSING SIZESAE number 1. 4.1.2 PILOT BEARING REQUIREMENTSCurrent 6306 size pilot bearing per SAE J1731.4.1.3 TRANSMISSION INPUT SHAFT SIZE60 mm (2.362 in) diameter shaft size with involute spline ha
21、ving TBDnumber of teeth and a 30 mm (1.181 in) diameter front pilot.4.2 Requirements Under Current StudyParameters which may change, but are not currently defined are asfollows:4.2.1 FLYWHEEL SIZEThe flywheel may be larger in diameter and have a higher thermal mass. The 430 mm(17in) nominal size is
22、considered as a practical maximum.4.2.2 CLUTCH SIZEThe clutch may need to be larger in diameter and of greater thermal mass.4.2.3 CLUTCH DAMPER REQUIREMENTSThe dampers may need to be larger in diameter and thicker to allow use oflarger diameter springs to maintain correct torque capacity while using
23、 a soft spring rate.4.2.4 RELEASE BEARING SIZEThe larger input shaft size will require an increased release bearing size. Thislarger size will increase the dimension across the housings anti-rotation flats.4.2.5 RELEASE YOKE SIZE AND PLACEMENTThe release yoke will need to be wider to conform to the
24、wider bearinghousing and placed at a greater distance above or below the input shaft to clear the larger release bearing.4.2.6 CLUTCH BRAKE SIZE AND SPLINED ATTACHMENTThe brake friction facing size may need to be increased indiameter to provide increased capability for higher inertia. Connection to
25、the input shaft may be through ameans which will delete the two long slots in the input shaft. The current lead approach is to use a dedicatedinvolute spline.4.2.7 CLUTCH HOUSING LENGTHThe new flywheel and clutch size requirements may require a longer clutch hous-ing for adequate clearance.4.2.8 TRA
26、NSMISSION CLUTCH BRAKE SURFACEDimensions may need to be revised to conform to the newrequirements of 4.1.3, 4.2.6, and 4.2.7.PREPARED BY THE SAE TRUCK AND BUS CLUTCH SUBCOMMITTEEOF THE SAE TRUCK AND BUS CHASSIS AND POWERTRAIN COMMITTEECopyright SAE International Provided by IHS under license with SA
27、ENot for ResaleNo reproduction or networking permitted without license from IHS-,-SAE J2408 Reaffirmed JUL2002RationaleNot applicable.Relationship of SAE Standard to ISO StandardNot applicable.ApplicationAlthough not limited to, these clutch requirements are normally used on trucks considered asHeav
28、y Duty (Class 8).This SAE Information Report defines and discusses clutch and related component configurations whichwill become the subject of future SAE Recommended Practices to promote standardization of clutchinstallations and mounting dimensions for use with pull-type heavy-duty clutches.Referen
29、ce SectionSAE J373Housing Internal Dimensions for Single- and Two-Plate Spring-Loaded ClutchesSAE J617Engine Flywheel Housing and Mating Transmission Housing FlangesSAE J1463Pull-Type Clutch-Transmission Installation DimensionsSAE J1479Automotive Pull Type Clutch TerminologySAE J1731Pilot Bearings f
30、or Truck and Bus ApplicationsSAE J1806Clutch Dimensions for Truck and Bus ApplicationsSAE J1857Flywheel Dimensions for Truck and Bus ApplicationsDeveloped by the SAE Truck and Bus Clutch SubcommitteeSponsored by the SAE Truck and Bus Chassis and Powertrain CommitteeCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-
