Measurement and Characterization of Anti-shudder Properties in Wet Clutch Applications

Wet clutches operating under low velocity and continuous sliding are increasingly important in vehicle transmissions. This presents new challenges in improving anti-shudder properties of the clutch system.

In order to determine anti-shudder properties the friction-velocity relationship is generally examined. The friction-velocity characteristics are however influenced by the way they are measured, and the measurement methods differ between different standards and OEM approvals, thus making direct comparisons of the anti-shudder requirements difficult.

This study investigates how different parameters influence anti-shudder properties. Results show how the obtained friction-velocity characteristics are influenced by the choice of different test procedures and parameters.

Methods for presenting the anti-shudder properties are compared for the different cases and a method for evaluation of the properties is suggested. Presenting data using the proposed method makes comparison of results obtained from different measurements easier or even possible.