Effects of tooth modifications on the dynamic characteristics of thin-rimmed gears under surface wear

Considering the thin rim structure and gear tooth modifications, a three-dimensional wear prediction model is proposed. Unitizing the proposed model, the contact pattern and the wear distribution are analyzed. For gear pairs with asymmetric rim structure, obvious stress concentration will lead to the severe wear on one edge of the gear tooth. Aiming at balancing the wear distribution and reducing vibration, an optimization scheme of the tooth modification (including the tip relief and the helix angle modification) is proposed. After adopting tooth modifications, the severe wear at one edge is almost eliminated. The fluctuation of the transmission error decreases significantly. The dynamic characteristics of thin-rimmed gears over the whole wear process are analyzed. It is found that the tooth modification is beneficial to shorten the running-in period and decelerate the failure process in the period of performance degradation.