This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Development of Equipment for Evaluating Brake Shim Damping under Actual Conditions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published September 18, 2016 by SAE International in United States
Annotation ability available
Brake squeal is an uncomfortable noise that occurs while braking. It is an important issue in automobile quality to prevent brake products from squealing. Brake shims are widely used to reduce squeal occurrence rate.
The anti-squeal effect of shims is quantified as damping properties measured with a bending mode tester, instead of repeating many dynamometer tests. However, there are cases where measurement results have less correlation to actual squeal suppression rate. Therefore, the evaluation of the anti-squeal effect with a dynamometer or on an actual car is needed until the best shim can be selected.
To improve the predicted accuracy of the anti-squeal effect, the difference between measurement conditions and actual braking conditions of shims, was focused on. The bending mode tester measures loss factor under pressure-free conditions, even though shims are compressed by pistons or cylinders towards the backplate of the pad. From this view-point, new evaluation equipment was developed for brake shims’ damping property under pressure load.
For measurement with the developed method, two shims, which had the same structure except for the material difference of viscoelastic layer between two steel plates, were prepared. The measurement results of both two shims showed that the loss factor had low dependencies on the pressure load. It seems that the loss factor of the viscoelastic material has low pressure dependency. On the other hand, it was confirmed that the loss factor of them had the frequency dependency and the dependency differs by the materials of the viscoelastic layer.
|Technical Paper||Eliminating Piston Slap through a Design for Robustness CAE Approach|
|Technical Paper||Correlation of Simulated and Measured Noise Emissions and Unsteady Gas Dynamic Flow from Engine Ducting|
CitationAoki, Y., Kanehira, Y., and Nishizawa, Y., "Development of Equipment for Evaluating Brake Shim Damping under Actual Conditions," SAE Technical Paper 2016-01-1918, 2016, https://doi.org/10.4271/2016-01-1918.
- SAE International Surface Vehicle Recommended Practice Brake Insulator Damping Measurement Procedure SAE Standard J3001 Feb. 2011
- JIS G0602 Test Methods for Vibration-Damping Property in Laminated Damping Steel Sheets of Constrained Type 1993
- Nishizawa , Y. , Wakamatsu , S. , Yanagida , H. and Tamura , Y. Study of Dynamic Pad Stiffness Influencing Brake Squeal SAE Technical Paper 2007-01-3956 2007 10.4271/2007-01-3956
- Oura , Y. , Kurita , Y. , Nishizawa , Y. , and Kosaka , K. Comparison of Pad Stiffness under Static Pressure and Vibration with Small Amplitude SAE Technical Paper 2012-01-1818 2012 10.4271/2012-01-1818
- Aoki , Y. , Nishizawa , Y. , Kurita , Y. , and Oura , Y. Friction Coefficient Variation at Minute Vibrating Velocity between Brake Pad and Disc Rotor SAE Paper, 2013-01-2041 2013 10.4271/2013-01-2041
- Aoki , Y. , Nishizawa , Y. , Kurita , Y. , and Oura , Y. Friction Coefficient Variation at Minute Vibrating Velocity between Brake Pad and Disc Rotor Euro Brake 2014 2014