400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (724) 776-4841 Fax: (724) 776-0790 Web: www.sae.org SAE TECHNICAL PAPER SERIES 2007-01-3749 Dynamic Analysis of Damper System in Torque Converter Taejun Park, Jaehoon Song, Jaeduk Jang and Insik Joo Korea Powertrain Co., LTD. 14th Asia Pacific Automotive Engineering Conference Hollywood, California, USA August 5-8, 2007Downloaded from SAE International by University of Minnesota, Monday, July 30, 2018The selection for publication of this manuscript is based on standard practices and guidelines of the originating country’s engineering and scientific society in the Asia Pacific region. All rights reserved. No part of this 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. For permission and licensing requests contact: SAE Permissions 400 Commonwealth DriveWarrendale, PA 15096-0001-USAEmail: [email protected]: 724-776-3036Tel: 724-772-4028 For multiple print copies contact: SAE Customer ServiceTel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (outside USA)Fax: 724-776-0790Email: Customer [email protected] ISSN 0148-7191Copyright © 2007 SAE InternationalPositions and opinions advanced in this paper are those of the author(s) and not necessarily those of SAE.The author is solely responsible for the content of the paper. A process is available by which discussions will be printed with the pap er if it is publishe d in SAE Transactions. Persons wishing to submit papers to be considered for presentation or publication by SAE should send themanuscript or a 300 word abstract of a proposed manuscript to: Secretary, Engineering Meetings Board, SAE. Printed in USADownloaded from SAE International by University of Minnesota, Monday, July 30, 2018Copyright © 2007 SAE International ABSTRACT This paper presents a newly proposed damper system in torque converter to minimize the vibration in powertrain system. The lock-up clutch in torque converter makes engine and transmission connected directly. When the lock-up clutch is engaged, the torque fluctuation of engine is attenuated by the damper system. This function decides the vehicle powertrain dynamic characteristics. To calculate the dynamic characteristics of vehicle, the vehicle model with a six-cylindered diesel engine and eight-speed A/T and three damper systems (conventional damper, turbine damper and new damper system) were structured by using AMESim® that is a commercial S/W. At first, the proposed damper system was analyzed by using the damper spring stiffness of previous damper system. New resonance frequency was appeared around 45Hz which didn’t exist in previous damper system. However, this resonance frequency was critical to the dynamic characteristics of the vehicle because engine operation range was between 40Hz and 250Hz. Therefore, this resonance frequency should be excluded from engine operation range. For solving this problem, the stiffness of damper spring was changed by using the stiffness equation proposed by regression analysis. As a result, new resonance frequency could be excluded from engine operation range, and the magnitude of frequency response function of the new damper system was less than that of the previous damper system. The torque and speed fluctuations of the vehicle model with new damper system were also reduced. INTRODUCTION The demand for the silence and the comfort of the vehicle is coming to be higher and higher. Not only the performance and the durability of the vehicle but also the emotional quality like the vibration and the noise have been significant factors when the customer are going to choose the vehicle model1). However, it is not easy to solve the NVH (Noise, Vibration, Harshness) problem because the root cause and propagation route of the vibration and noise are comple