The impactof systemparametersof the geartransmission systemin the role of an external excitationon the systemdynamics is studied

and a theoretical basis is provided in order to avoid gearworking in a chaotic state.A single degree of freedomspurgeardrive systemisviewed as the research object

a nonlineardynamical model is established

which is regarded the nonlinearfactors of internal excitation and external excitation.Besides

a Runge-Kutta numerical method for solving the nonlinear dynamic equations of the system is applied to the research

the period and chaotic state of the gear system in an external excitation are analyzed

and a theoretical guidance for the design and manufacture of the gear and get better performance is provided.