400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (724) 776-4841 Fax: (724) 776-5760 Web: www.sae.org 2005-01-0551 Development of Direct Electromagnetic Clutch System Rikiya Kunii, Akihiro Iwazaki, Shigenobu Sekiya, Yutaka Kanno, Katsuhiro Kitamura and Yasuji Shibahata Tochigi R&D Center, Honda R&D Co., Ltd. Reprinted From: Transmissions and Drivelines Symposium–4WD/AWD (SP-1979) 2005 SAE World Congress Detroit, Michigan April 11-14, 2005 SAE TECHNICAL PAPER SERIESDownloaded from SAE International by Univ of California Berkeley, Wednesday, August 01, 2018The Engineering Meetings Board has approved this paper for publication. It has successfully completed SAE’s peer review process under the supervision of the session organizer. This process requires aminimum of three (3) reviews by industry experts. 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] Tel: 724-772-4028 Fax: 724-772-4891 For multiple print copies contact: SAE Customer ServiceTel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (outside USA)Fax: 724-776-1615Email: [email protected] ISSN 0148-7191Copyright © 2005 SAE International Positions 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 discussionswill be printed with the paper if it is published in SAE Transactions. Persons wishing to submit papers to be considered fo r presentation or publication by SAE should send the manuscript or a 300 word abstract to Secretary, Engineering Meetings Board, SAE.Printed in USADownloaded from SAE International by Univ of California Berkeley, Wednesday, August 01, 20182005-01-0551 Rikiya Kunii, Akihiro Iwazaki, Shigenobu Sekiya, Yutaka Kanno, Katsuhiro Kitamura and Yasuji Shibahata Tochigi R&D Center, Honda R&D Co., Ltd. Copyright © 2005 SAE International ABSTRACT Honda has developed the SH-AWD （Super Handling-All Wheel Drive) system (Ref.1), the world’s first 4WD system capable of continuous ly and variably distributing torque to all four wheels of the vehicle. The use of this system enables torque to be employed in the control of the yawing moment and the application of control to equalize the load ratio between all the wheels of the vehicle. This results in higher turning stability and increased turning limit performance. These forms of control require a highly responsive actuator capable of controlling torque with a high degree of accuracy. A direct electromagnetic clutch in which solenoid attraction acts directly on the clutch was newly developed to satisfy the function described above. Detection of the solenoid air gap is required to enable high-accuracy control of solenoid attraction. A search-coil-type -sensor based on a new concept was developed and employed to enable detection of the solenoid gap. INTRODUCTION Recently, demands are rising not only for passive, but for active as well, technology to enhance the safety of vehicles. (Ref.2) As a method of actively enhancing the handling and stability of vehicle, it has been shown that direct control of the vehicle yaw moment utilizing the difference between the left and right drive forces is effective for increasing the cornering performance, handling and stability of vehicle. (Ref.3, 4) In order to realize this, t he SH-AWD system was newly developed. This system uses a pair of left and right clutches, installed in the rear drive unit, to enable drive force to the front and rear wheels, and also to the left and right rear wheel to be controlled independently. As the actuator for cont rolling the abov