Investigation of assembly, power direction and load sharing in concentric face gear split-torque transmission system

As a special transmission mechanism used in aeronautical transmission field, a concentric face gear split-torque transmission system (CFGSTTS) is investigated in this study, with the focus on the work performances of the system including assembly, power direction and load sharing. Considering the complicated layout with multiple asymmetric power branches, the assembly condition of CFGSTTS is deduced and validated. To simulate this closed-loop system whose power directions are unknown in advance, a new finite element model which greatly differs from the conventional model in analytical step, boundary condition and grid division is developed. By the application of the new model, the power directions of branches in CFGSTTS are determined. On the premise of meeting the assembly conditions, the effect of factors including load condition, distribution angle, layout form and the number of idlers on power directions in CFGSTTS is researched, and the impact of those factors on load sharing is also explored. The results reveal that the power directions in CFGSTTS are alterable, and the load sharing coefficients are affected obviously by structural parameters.