Research on load-sharing characteristics of six-branch herringbone gear transmission system

With the continuous development of high-speed and high-power gear transmission technology, as well as the new demand for vibration and noise reduction in high-speed and heavy-duty gear transmission systems in fields such as aviation and navigation, the herringbone gear branch transmission system is subject to higher requirements in terms of its dynamic characteristics. Therefore, it is necessary to conduct research on the dynamic characteristics of high-power and high-torque herringbone gear branch transmission systems. Based on the lumped parameter method, a bending-torsion coupling dynamic model of the transmission system is established, and a calculation method for load-sharing coefficients (LSCs) is proposed. The LSCs are obtained for each gear pair in the same meshing period of the transmission system that is under the interaction of time-varying internal excitation. The meshing force of the six-branch gearing system was calculated in ADAMS to verify the validity of the established dynamic model. The study results indicate that errors have a negative impact on the sharing performance. To maintain a sharing coefficient below 1.15, the manufacturing and installation errors of gears Z5 and Z6 should be restricted to 9 mu m and 7 mu m, respectively. Special attention should be given to gear Z5 in terms of support stiffness, with a value of 1 x 108 N/m being the most favorable. During the system design, the initial phase of the installation error should be considered and preferably selected near 180 degrees. Additionally, the system exhibits easier load sharing with higher input power. The optimal torsional stiffness of the duplex shaft is 5 x 107 N/m, while the optimal bending stiffness is 5 x 108 N/m. This study aimed to provide a theoretical foundation for the design and optimization of marine high-power gear transmission systems.