Effect of clearance configuration on gear system dynamics

Abstract

Depending on the presence and position of a switch control element such as a synchronizer or sleeve in a multi-speed transmission, a gear system with gear backlash can be in one of three clearance configurations: no engaging clearance, engaging clearance at the input shaft, or engaging clearance at the output shaft. In this article, the influence of clearance configuration on gear system dynamics is investigated using the oscillating component of the dynamic transmission error as the dynamic response. The dynamic responses are studied over a wide frequency range by speed sweeping to examine the nonlinear behavior using numerical integration. Gear systems in all three clearance configurations show typical nonlinear behavior, such as multiple resonances, softening nonlinearity, jump phenomena, and chaotic motion. The presence of engaging clearance clearly affects the nonlinear characteristics, including resonance amplitudes, jump frequency, overlap width of primary resonance, and degree of chaos. Compared with the NC configuration, the resonance amplitudes for the CI and CO configurations decrease, while fluctuations increase. The resonance amplitudes and fluctuations for the CI configuration are both greater than those for the CO configuration, indicating that system vibration is greater when the clearance is far from the large inertia.