In this paper, an improved mesh excitation calculation method with random cumulative pitch errors is constructed, and a lumped-parameter model for the herringbone planetary gear system is established. Subsequently, the action of random cumulative pitch errors on mesh excitations under different loads is studied. Furthermore, the dynamic mesh forces for all mesh pairs of the herringbone planetary gear system are investigated in detail, considering the effects of random cumulative pitch errors.  

The paper studies the three-dimensional contact finite element model of a double helical gear-shaft-bearing system based on the load-bearing contact analysis of the tooth surface. The results show that the tooth surface bearing contact of the system has the phenomenon of partial load due to the supporting deformation, and the unmodified herringbone gear has obvious contact stress concentration, which can be effectively improved by gear tooth modification.

This paper introduces several types of multi-engine multi-gearbox marine gearing. A total of two dynamic modeling methods are proposed to predict the coupled vibration of these systems. The dynamic models of four engines with two shafts under different working conditions are established, and the effects of coupling, speed, configuration and power loss on the system vibration are studied.