Assessment of structural behavior of torque converter dampener

Abstract

A Torque Converter Dampener is a primary component for transmittal of power between the Engine and the Transmission. It comprises of three major components – driving cage plates, driven cage plates and set of springs. Being a spring based system, it provides a smooth conversion of torque from engine to the driveline. When the vehicle performs a gearshift, these springs damp the driveline oscillations and they get locked when the vehicle runs at a higher speed. A Torque Converter Dampener assembly is typically subjected to high torque and centrifugal loading and sometimes, there is a chance of breaking of the springs under operating loading conditions. This paper explains detailed method of analyzing Torque Converter Dampener using Finite Element Analysis. Cage plates and springs are modeled accurately with interactions and boundary conditions properly defined similar to actual hardware, in order to capture the physics of the system. As the problem is highly complex in nature, material non linearity, temperature effect and effect of dynamic fluid pressure are not taken into consideration. The analysis process takes care of the spring’s installation followed by applying centrifugal force and torque in alternating sequence. Similar method is repeated for different spring orientation to find out the worst case model and loading sequence. High stress locations on springs and Driving/Driven cage plates are identified and correlated with the actual hardware test results.