Investigation of instantaneous rotation center and inertia of planet gear based on the mechanism in the three-axis driving planetary gear train

Abstract

Planetary gear trains are presently widely used in various machines owing to their many advantages. They, however, suffer from problems of noise and vibration due to their structural complexity. Moreover, their dynamic characteristics are yet to be fully understood. Although several studies have been conducted on two-axis driving and displacement of planet gear, none has considered three-axis driving. The general driving conditions of a planetary gear train, including during three-axis driving, were investigated based on the theory of instant center, and ideal driving condition is proposed based on the experimental result which was tested on an original fully wireless test stand, in the previous study. In the present study, the centrode variation of the planet gear due to the speed fluctuations of the ring gear and carrier, and inertia of planet gear about instantaneous center were investigated as a cause of efficiency reduction.