Release Bearing Characteristic of Diaphragm Spring Under Dynamical Condition 2019-01-1424
Diaphragm spring design have a critical importance on engagement and disengagement mechanism for a clutch system. The release bearing load characteristic of diaphragm springs determines the quality of disengagement. Bearing load may chance significantly especially under dynamic conditions compared to static conditions. For instance, a significant drop in bearing load may be experienced under high engine velocities. This is an undesirable situation in terms of clutch performance. This problem has not been addressed in technical literature. Therefore, new design of diaphragm spring becomes necessary to avoid weakening of clutch performance as the engine speed increases which lead to highly dynamic conditions. In this study, the effect of some design parameters for diaphragm springs such as outer radius and embossing are investigated using nonlinear finite element modeling. Three different outer radius with and without embossing were analyzed under boundary conditions representing actual diaphragm tests. Based on the results of FEA, it is concluded that unwanted load drops increases as the outer radius increases while embossing also leads to higher load drop. On the other hand, embossing increases the stiffness of diaphragm fingers and therefore a smaller deformation and a more long-lasting clutch load performance. As a result, an optimum design is required as the diaphragm outer radius increases for a robust disengagement behavior.
Alper Karaduman, Huseyin Lekesiz, Ali Yildiz
Valeo Otomotiv Sanayi ve Ticaret A.S., Bursa Teknik Universitesi, Bursa Uludag University