Generation mechanism and evolution of five-state meshing behavior of a spur gear system considering gear-tooth time-varying contact characteristics

Teeth disengagement or back-side teeth engagement induced by backlash reduces the transmission quality and dynamic performance of gear systems, accurate interpretation multi-state meshing behavior can provide guidance for structural optimization evaluation. Therefore, system is elaborated. A new nonlinear model a spur with five-state established based on time-varying contact ratio. The stiffness considering elastic teeth, temperature rise lubrication are included in model. clearly characterized constructing five Poincaré maps, its generation mechanism revealed using force time history, relative displacement history phase portrait. bifurcation evolution analyzed under effects load factor, frequency error coefficient. results show that mutation direction leads to disengaging single- double-tooth contact, forming behavior. Bifurcation caused parameter changes greatly affects behavior, particularly grazing decrease number disengagement. Chaotic trajectory expansion inspires vibration system. Previous models could not reveal these phenomena due ignoring