INTERNATIONAL^ 400 COMMONWEALTH DRIVE, WARRENDALE, PA 15096-0001 U.S.A. The Mercedes-Benz 5-Speed Automatic Transmission Targets and Comparison of Concepts H. J. Schoepf and G. Juergens Mercedes-Benz AG Reprinted from SP-837 - Dynamic Characteristics of Today's Passenger Car Transmissions Passenger Car Meeting 9 -/J -or) and Exposition , , I - Dearborn, ~ichigan September 17-20, 1990 Downloaded from SAE International by University of Edinburgh, Saturday, August 25, 2018The appearance of the ISSN code at the bottom of this page indicates SAE's consent that copies of the paper may be made for personal or internal use of specific clients. This consent is given on the condition, however, that the copier pay a $5.00 per article copy fee through the Copyright Clearance Center, Inc., Operations Center, 27 Congress St., Salem, MA 01 970 for copying beyond that permitted by Sections 107or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such as copying for general distribution, for advertising or promotional purposes, for creating 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 Service Department. To obtain quantity reprint rates, permission to reprint a technical paper or permission to use copyrighted SAE publications in other works, contact the SAE Publications Group. - - -- -- -- - - -..-- . -- -- -- - - - -- - - -- -- - -- .- - -- - - AH SAE papers are --. - -.. - == --.- -. , - - . -- -- - abstracled andhdexedln - - --A - - --- - - -- - -- the SAE Global Mob##~ Database. --- -- --- . ------- - -- -- - ----- =-= -- -- -- -- -- -- -- -- - - - - SAE GLOBAL MOBLrrY DATABASE @ No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior writ- ten permission of the publisher. ISSN 01 48-7191 Copyright 1990 Society of Automotive Engineers, Inc. Positions and opinions advanced in this paper are those of the Persons wishing to submit papers to be considered for presen- author(s) and not necessarily thoseof SAE. The author is solely tation or publication through SAE should send the manuscript responsible for the content of the paper. A process is available or a 300 word abstract of a proposed manuscript to: Secretary, by which discussions will be printed with the paper if it is Engineering Activity Board, SAE. published in SAE Transactions. For permission to publish this paper in full or in part, contact the SAE Publications Division. Printed in USA Downloaded from SAE International by University of Edinburgh, Saturday, August 25, 2018The Mercedes-Benz 5-Speed Automatic Transmission Targets and Comparison of Concepts H. J. Schoepf and G. Juergens Mercedes-Benz AG Since the introduction of the 4-speed automatic transmissions W4A040 in 1979 and W4A020 in 1981, more than 50% of Mercedes-Benz cars have been equipped with automatic transmissions. These transmissions have undergone continuous development since their introduction. Due to engine/transmission management, the kick-down shift points are elec- tronically influenced, the shift com- fort is improved partially by ignition timing manipulation. During the warm-up phase the shift points are raised via output signals from the electronic en- gine system to improve exhaust gas emissions. In this paper considerations are explained which resulted in supple- menting the proven four-speed transmis- sion with a five-speed transmission. 1. OBJECTIVES AND CONCEPT COMPARISONS 1.1 Starting device When investigating the transmission gear ratio steps during the design phase of a new transmission it has to be checked whether the torque converter is still needed as a starting-off aid. The continuously variable transmissions (CVT) which recently have been intro- duced on the market, are equi