Vibratory Behavior in Multi Stage Helical Gear System. Theoretical Study on the Coupled Vibration of the Intermediate Axis.

Abstract

Many of industrial gear systems are the multi-stage and with two gear pairs on the intermediate axis. In such multi-axes systems, two meshes on the intermediate axis cause coupled vibration. In this paper, the behavior of coupled vibration of such helical gear system composed of three axes will be theoretically examined. The exciting force caused by axial movement of the distributed load on the tooth flank will be considered as well as the exciting force caused by tooth flank error and by the change of tooth spring stiffness. As a result, it will be clarified that the intermediate axis has two vibratory modes; one is the coupled vibration between tooth normal displacements at both of two gear pairs. The other is the coupled vibration between rotational displacement in the plane of action at the first gear pair and the tooth normal displacement at the second gear pair.