The lightweight design of the gear system is the current tendency. The gearbox housing is modeled as a rigid body and is neglected in the gear dynamic analysis. It is of great significance to introduce the gearbox housing flexibility into the dynamic analysis and analyze the influence of the gearbox housing flexibility on the dynamic behaviors of the gear transmission system, as this can provide important instructions for the lightweight structure design of the housing. The gear–rotor–bearing model and the gear–rotor–bearing–housing model are established by the finite element node method. A Timoshenko beam element is used to represent the shafts. To illustrate the housing effect, two kinds of housing model are established: one tends to be rigid and the other to be flexible and lighter. The housings are simplified as a super element obtained by the dynamic substructure method. Natural frequencies and dynamic responses are illustrated to indicate the effects of housing flexibility. Comparisons of numerical results show that the rigid housing can be neglected for its little effect on the dynamic analysis. The flexibility of the housing slightly reduces the natural frequencies of the gear transmission system, and the maximum reduction is 6.05%. Meanwhile, the amplitudes of the first two resonance peaks of the dynamic transmission error decrease by 9.5% and 5.05%. Besides, more response peaks emerge at higher speeds when the flexibility of housing increases. The complete phenomena of dynamic behaviors of the gear transmission system can be obtained by considering the housing flexibility.
The bearing internal load distribution and fatigue life estimation are accomplished based on the bearing static model at present, ignoring the gear engagement. Besides, bearings are modeled as a linear spring in gear dynamic models, failing to analyze bearing internal load. This article aims to study the bearing internal load fluctuation and corresponding bearing life in gear systems. A nonlinear dynamic model of the gear-bearing system is built, considering the time-varying mesh stiffness, the static transmission error, backlash, bearing clearance, and the nonlinear bearing force. The dynamic model is capable of calculating the bearing internal load. Based on the internal load, fatigue life is acquired using the linear damage theory. The numerical results show that the gear engagement has a significant influence on the bearing internal load analysis, in which periodic fluctuation is related to the mesh frequency and shaft frequency, resulting in the bearing life affected by gear meshing. Compared with the fatigue life predicted under the bearing static model, evident deviations are observed, pointing to the significant role of the gear engagement in the analysis of fatigue life estimation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.