Gear drive system is a complex structure system which includes gear pair, drive shaft, bearing, box and other components. The dynamic research of gear drive mainly focuses on three aspects: parameter excitation (time-varying rigidity, tooth profile error, gear backlash, tooth surface friction, etc.), system inherent characteristics (mode, vibration, damping), dynamic response (vibration and noise).
The inherent dynamic characteristics of a shaped gear drive system or product are determined by itself, but their dynamic responses vary greatly under the excitation of different factors formed under different operating conditions and applications.Dynamic excitation of gear drive can be attributed to two directions of meshing line and tooth friction. There are two excitation forces in the direction of meshing line, namely, tooth engagement force and tooth flapping force.Cyclic excitation of tooth meshing force is mainly caused by transmission error (TE) caused by time-varying stiffness and tooth profile error, which may lead to a single frequency tuning noise – Gear whine in the gear system.
The tooth flapping force excitation is formed by the reciprocating movement of driven gear between the backlashes under the non-loading condition of the gear. The flapping excitation directly generates the “click” low frequency knocking noise (Gear rattle).The dynamic excitation of tooth surface friction force is obvious when the tooth surface is damaged in open drive or tooth surface lubrication is poor, and it also affects the excitation in the direction of meshing line, thus the dynamic response of the system becomes complicated.In addition, when multiple engagement excitations exist in the gear system, they will influence each other to form new exciting factors, which make the system response more complex.It can be seen that different excitation factors correspond to different dynamic response characteristics. Under various excitation factors, taking into account the dynamic analysis of tooth friction, time-varying stiffness, tooth profile error, tooth side clearance and other factors, a deep discussion of the dynamic characteristics of gear transmission system and the influence of related factors will be of great significance to the low vibration and noise design of gear system.
Starting from different exciting factors, taking typical gear drive system as research object, combining with vibration and noise problems in engineering practice, relevant theoretical, experimental and engineering application research will be carried out on exciting mechanism and corresponding vibration and noise reduction methods.