Effects of Eccentricity Defect and TOOTH CRACK on Two-Stage Gear System Behaviour
Lassâad WALHA, Jamel LOUATI, Tahar FAKHFAKH and Mohamed HADDAR
Unit of mechanics, modelling and production U2MP
National school of engineers of Sfax, BP.W. 3038 - TUNISIA
The modelling of the dynamic behaviour of a plane model of two-stage gear system is formulated. The excitation is induced by the periodic variations of the mesh stiffness. The mesh phasing is related to the number of teeth. This case describes the real working of the gearings. The calculation of the dynamic response is done by a step-by-step time integration method (Newmark method). Severe working conditions can lead to the system failure. The eccentricity defect is then introduced in the model. The case of tooth crack occurring during running is also introduced. The dynamic behaviour of the healthy system and the defected one are compared both in the time domain and in the frequency domain. An analysis of the effects of these defects on the two-stage gear system dynamic behaviour is treated in order to extract their features. .