218 A Study on Shudder Vibration of AT Lock-up Clutch Systems

Abstract

In the torque converter of the automatic transmission car, the mechanism of lock-up clutch that improves fuel cost is used. However, the shudder vibration sometimes occurs. The shudder vibration is a torsional vibration, and is caused by the friction at the lock-up clutch. When the shudder vibration occurs, the tires vibrate in the torsional direction which leads to the vibration of the car. Therefore, the shudder disturbs the comfort for the passengers. In this report, the mechanism of the shudder was clarified by the experiment and theoretical analysis, and the countermeasure using the dynamic absorber is also analyzed. The results of the experiments qualitatively coincide with those of the numerical analysis.