A new analytical model for clutch system modeling and design optimization. 2019-01-0840
In manual transmission vehicles, Clutch has a direct interaction with driver and plays a major role in defining the drivability and NVH of a vehicle. These key performances depend on interaction of various nonlinear springs in clutch cover and disc assemblies. For a car manufacturer, it’s important to optimize vehicle performance based on individual characteristics of clutch springs in a fast and easy way.
Torque transmissibility, which primarily determines launch quality, depends on combined response of clutch cushion spring, diaphragm spring and cover pressure plate lift off characteristics. Similarly, clutch pedal load characteristic depends on combined response of cover diaphragm and cushion springs. The individual design and interaction of these springs influence the multiple vehicle performance parameters. Often much iteration is required before achieving optimal design of springs.
Limited information has been published in past for estimating the actual response of set release load, torque build up and pressure plate lift off. A state of the art analytical model has been developed by modeling the diaphragm and cushion spring with exponential equations. Based on these models, response functions in form of implicit equations for set release load, torque build up and pressure plate lift off have been derived. Results achieved from these response functions are correlated. Then, by considering the desired pedal characteristics and torque build up behavior as objective functions, a multi-objective Pareto optimization problem is solved. It is shown that design optimization process is simplified.