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 entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising there
2、from, 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 2011 SAE International All rights reserved. No part of this publication m
3、ay 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: +1 724-776-4970 (outside U
4、SA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedbackon this Technical Report, please visit http:/www.sae.org/technical/standards/J3001_201102SURFACEVEHICLERECOMMENDEDPRACTICEJ3001 FEB2011 Issued 2011-02 Brake Insulator Dampi
5、ng Measurement Procedure RATIONALE Brake pad insulators are a primary device used in the control of brake squeal for passenger cars throughout the world. Each insulator damping is tuned for a specific application. Because there is currently no recognized standard for measuring insulator damping, the
6、 SAE Brake NVH Standards Committee identified the need to establish a measurement standard that would allow one to accurately and consistently measure insulator damping. 1. SCOPE This procedure is applicable to modes between 1500 and 15 000 Hz. The parameters measured with this procedure are defined
7、 as the damping factor, for first three bending modes of the beam. The procedure will focus on bending modes only.1.1 Purpose This SAE Recommended Practice is intended to establish a standardized and repeatable method for performing damping measurements on a brake insulator. 2. REFERENCES 2.1 Relate
8、d Publications The following publications are provided for information purposes and are not a required part of this SAE Technical Report. D. J. Ewins, Modal Testing - Theory, Practice and Application, Second Edition, 2000, Research Studies Press LTD, England B single degree of freedom identification
9、 method. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J3001 Issued FEB2011 Page 5 of 7FIGURE 3 - EXAMPLE OF AN FRF (TOP) AND COHERENCE FUNCTION (BOTTOM) 8. SUMMARY OF RESULTS There are differe
10、nt ways to summarize the data: - For each temperature, plot the FRF curve from 1500 to 15 000 Hz as shown in Figure 3. - For each temperature and each mode, tabulate the frequency and damping (Table 1). - Summarize on one Excel graph the frequency and damping values with temperature for the 3 beam m
11、odes (Figure 4). - Generate a 3D colour plot, temperature, frequency and damping, using commercially available software like Matlab (Figure 5). TABLE 1 - SUMMARY OF DAMPING WITH TEMPERATURE AND MODE N Test Date: _Test Conducted By: _ Insulator Code/Type: _ Sample n: Pad ID Mode 1 Mode 2 Mode 3 Notes
12、 Temperature (C) Nat. Freq., Hz Damping (%) Nat. Freq., Hz Damping (%) Nat. Freq., Hz Damping (%) Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J3001 Issued FEB2011 Page 6 of 705,00010,00015,00
13、020,000-20 0 20 40 60 80 100 120 140 160Temperature (C)Frequency (Hz)0.000.010.101.0010.00Damping (%)FIGURE 4 - SUMMARY OF THE DAMPING WITH TEMPERATURE AND FREQUENCY FIGURE 5 - SUMMARY OF THE DAMPING WITH TEMPERATURE AND FREQUENCY Copyright SAE International Provided by IHS under license with SAENot
14、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J3001 Issued FEB2011 Page 7 of 7The data can also be summarized by: - The temperature and frequency range where the damping value is =1% - Focusing on one mode only - One damping average value for the whole test - Mi
15、nimum damping f, T - Maximum damping f, T 9. NOTES 9.1 Marginal Indicia A change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left
16、of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. PREPARED BY THE U.S. BRAKE NOISE VIBRATION AND HARSHNESS STANDARDS COMMITTEE Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
