Design and elastic contact analysis of a friction bearing with shape constraint for promoting the torque characteristics of a dual mass flywheel

A friction bearing with shape constraint is introduced into a dual mass flywheel (DMF) with single-stage stiffness to improve the counter torque of the DMF. In polar coordinates, a displacement-based method of elasticity, which is derived in this paper, is applied to establish the calculation model of the elastic contact between the secondary flywheel and the friction bearing block. With the known displacement boundary conditions, the distributions of strain and stress on the contact region and the torque characteristics generated by the contact effect are obtained. By theoretical calculation and experiments, the introduced friction bearing with shape constraint and design theory involved prove to be feasible for increasing the counter torque of the DMF, which makes the DMF well suited for more powerful engines. Meanwhile, the modified DMF with continuously variable stiffness characteristics still has low stiffness at small torsional angles, which ensures the DMF's performance of isolating the first-order resonance vibration so that the engine can operate at a low idle speed to reduce energy consumption.