Improvement of the vibro-acoustic behaviour of vibratory feeders for pasta by modelling and experimental techniques

Nowadays, the reduction of vibration and noise in mechanical systems is pivotal. In this scenario, this paper addresses the vibro-acoustical improvement of a pre-drying vibratory feeder for pasta by means of experimental and numerical vibration analysis. The moving parts of the pre-drying feeder are coupled with the structural base by means of leaf springs and the swinging motion is achieved by an eccentric-and-rod mechanism driven by an asynchronous motor. The oscillating motion leads to an unacceptable vibration level that often induces failures and extreme loudness. Operational vibrations have been measured as well as torsional oscillation of the main shaft by means of laser probe and zebra tape. Furthermore, a modal analysis of key components of the system has been carried out. In order to foresee the effects of design changes, an analytical dynamic model was developed and validated by experimental measurements. Exploiting the experimental and numerical results, several modifications have been carried out for vibration reduction. The noise and vibration level of the system has been significantly reduced and the effectiveness of vibration improvement has been experimentally verified.