SAE TECHNICAL PAPER SERIES 970679 Slipping Torque Converter Clutch Interface Temperature, Pressure and Torque Measurements Using Inductively Powered Radiotelemetry M. J. Throop and D. G. McWatt Ford Motor Co. Reprinted from: 1997 Transmission and Driveline Systems Symposium: Transmission Systems, Components, Gears and Friction and Fluid Materials (SP-1241) International Congress & Exposition Detroit, Michigan February 24-27,1997 400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (412)776-4841 Fax:(412)776-576 0 Downloaded from SAE International by University of New South Wales, Saturday, August 25, 2018The appearance of the ISSN code atthe bottom of this page indicates SAE's consent that copies ofthepapermay be made forpersonalorintemal use of specificclients. Thisconsent is given on thecondition however, thatthecopierpaya$7.00perarticlecopyfee through the Copyright Clearance Center, Inc. Operations Center, 222 Rosewood Drive, Danvers, MA 01923 forcopyingbeyond that permittedbySections 107 or108oftheU.S. Copyright Law. This consent does not extendtootherkinds of copyingsuchascopyingforgeneral distribution.foradvertisingorpromotional purposes, forcreating new collective works, or for resale. SAE routinely stocks printed papers for a period of three years following date of publication. Direct your orders to SAE Customer Sales and Satisfaction Department. Quantity reprint rates can be obtained from tie Customer Sales and Satisfaction Depart­ ment. To request permission to reprint atechnical paper or permission to use copyrighted SAE publications in otherworks, contactthe SAE PublicationsGroup. No part of this publication may by reproduced in anyform, in an electronic retrieval system orotherwise, without the prior written permission of the publisher. ISSN0148-7191 Copyright 1997 Society of Automotive Engineers, Inc. Positions and opinions advancedinthispaperarethoseoftheauthor(s)andnot necessarily those of SAE. The author is solely responsible forthe content of the paper. A process is available by which discussions will be printed with the paper if it is published in SAE Transactions. For permission to publish this paper in full or in part, contact the SAE PublicationsGroup. Persons wishingtosubmitpaperstobeconsideredforpresentationorpublication through SAE should send the manuscript or a 300 word abstract of a proposed manuscript to: Secretary, Engineering Meetings Board, SAE. Printed in USA Downloaded from SAE International by University of New South Wales, Saturday, August 25, 2018970679 Slipping Torque Converter Clutch Interface Temperature, Pressure andTorque Measurements Using Inductively Powered Radiotelemetry M.J. Throop andD.G. McWatt Ford Motor Co. Copyright 1997 Society ofAutomotive Engineers, Inc. ABSTRACT Torque converter clutch friction interface andautomatic transmission fluid (ATF) temperatures, pressure differ ence across theclutch piston, flow through thefriction material grooves, andengine crankshaft dynamic torque were measured fortypical operating conditions ona running transmission. The friction coefficient, clutch unit pressure, fraction ofheat rejected toATF flowing through thegrooves, andtime dependent thermal re sponse were determined. Simplified heat transfer cal culations were compared with thermal data. Clutch in terface temperatures were assessed asthey relate to theprocess offriction material and ATF degradation. The inductively powered radiotelemetry system was found tobearobust andpowerful toolforinvestigating continuously slipping clutch system performance. INTRODUCTION Inorder togain improved fueleconomy, auto matic transmission torque converter clutches arede signed tobypass thetorque path through thefluidcou pled impeller-turbine system infavor ofaparallel path from theengine directly