Dynamic behavior of a helical gear transmission system

This paper discusses the effect of variations in parameters and damping of gear structure on vibration of helical gear system. The effect of variations in geometry of gear web on vibration of gear system is presented. For example, when the thickness of a web is decreased from half tooth width to one eighth of tooth width, the dynamic load (acting on web) factor is reduced from 1.6 to 1.1, but the peak dynamic load (acting on gear tooth due to gear web torsional vibration) factor is increased from 1.15 to 1.28. The effect of web damping on vibration of gear system is presented. It can be easily seen that increase of web damping can reduce remarkably the peak dynamic loads acting on the gear web and gear teeth respectively due to web vibration. Finally, the research result is presented which appears to be contrary to what is generally believed. It is found that gear structure parameters--types of web arrangement, damping of web, dimensions of gear rim and web, have little effect on the dynamic loads acting on the gear tooth. This is because the gear system is excited through the gear teeth.