Host: The Japan Society of Mechanical Engineers
Name : Dynamics and Design Conference 2021
Date : September 13, 2021 - September 17, 2021
In the automotive industry, the silence and ride comfort of the car body have been markedly improved by the development of the hybrid vehicles and fuel cell vehicles. However, the complicated fictional vibration is caused in brake system by the pursuit of a high brake performance. In this study, hot judder is modeled as self-excited vibration due to the time delay caused by heat deformation of the disc, and the fundamental generation mechanism of hot judder is analyzed by a simple three degree-of-freedom system. The pad is modeled as an elastic area with a distributed contact spring. A stability analysis for this system was conducted, consider the effect of pad length on hot judder occurrence. From the results, it was confirmed that the vibration of the braking system caused by the fluctuation of the contact force between the disc and the pad causes the fluctuation of the surface expansion of the disc, and causes a larger fluctuation of the contact force with a time delay. Also, It was found that an appropriate pad length for each number of hot spots can reduce the growth of hot judder that occurs at a specific number of hot spots.
