Optimizing Automatic Transmission Clutch Lining Load Distribution Using Finite Element Analysis

A Finite Element Analysis technique was used to predict the clutch lining load distribution in automatic transmissions. This technique is explained and demonstrated on several clutch designs. The analysis shows the importance of rigid backing plates and optimum piston apply points. The benefit of tapered apply plates is also discussed. The importance of having a uniform clutch lining load distribution is described as it relates to clutch torque and energy capacity.

THE PURPOSE of this paper is to discuss the importance of clutch lining load distribution for automatic transmissions as it relates to torque and clutch energy capacity. The design variables that affect these will be presented. Clutch pack compliance versus rigidity will also be addressed. A finite element technique for calculating the clutch lining load distribution will be discussed. This technique will be demonstrated on several clutch designs. Based on the finite element analysis, recommendations for designing higher torque and energy density clutches will be made.