On the Running Noise of Toothed Belt Drive : 1st Report, Mechanism of Noise Generation

As the first step to find the noise reduction methods for toothed belt drive, the authors investigated the characteristics of the noise and its generating mechanism experimentally. The results obtained are as follows: (1) In general running condition the impact sound which is generated periodically with tooth meshing frequency is the most powerful component in the noise. And it was ascertained that the impact sound is caused by the collision of tooth tips of the driving wheel against bottom lands of the toothed belt. (2) When the belt tension is large enough the transverse vibration (string vibration) of belt resonates badly with the meshing frequency and this resonant sound sway the noise level. (3) In a case where both impact and resonant sound are not predominant, the toothed belt drive runs silent enough.