Research status of compound fault of gear transmission system abroad

Kahraman and Singh established a 3-DOF dynamic model. The nonlinear relationship between radial clearance and ruler side clearance of rolling bearing was considered. The nonlinear frequency response characteristics of gear rotor bearing system were studied. The meshing stiffness of gear was regarded as a fixed value in the model. On this basis, Kahraman and Singh take into account the time-varying characteristics of gear meshing stiffness. Baguet and jacquenot established the dynamic model of single-stage gear rotor rolling bearing system. Through the analysis of gear dynamic load, bearing dynamic load and bearing displacement, it is proved that the dynamic interaction between gear and bearing will occur.

Zeng et al. Established the nonlinear dynamic model of the gear shaft bearing box system by using the finite element method, analyzed the nonlinear dynamic response of the coupling system under the internal excitation of the tooth time-varying stiffness and machining error, and studied the influence of the coupling system’s displacement, velocity and acceleration response, as well as the influence of meshing stiffness and bearing support stiffness on the vibration response of the coupling system. Sawalhi and Randall A dynamic model of the combination of gear and rolling bearing is proposed to study the interaction between rolling bearing and gear with fault. In order to simulate this situation, the transmission shaft supported by rolling bearing and the whole gear system are modeled. Based on Hertz contact theory, the model connects the raceway displacement with the bearing load and considers the sliding between the components Move.

In order to study the influence of bearing defects on the vibration characteristics of gears and the influence of gear defects on the vibration characteristics of bearings, the vibration analysis of single-stage spur gearbox with defects in both gears and bearings was carried out, and a detection method for multi-component damage was proposed by using vibration signals. In order to explore the composite fault of gear bearing system, dhamende and Chaudhari have studied the composite faults such as inner and outer ring fault of rolling bearing, two corner damage of gear or three tooth angular loss of gear by experiment. Vibration measurement was carried out under different rotating speed and load conditions, and new composite fault features were extracted from continuous wavelet transform and discrete wavelet transform of vibration signal.

Gao and Zhang established a dynamic model of the gear rotor bearing system considering the factors such as backlash, transmission error, time-varying meshing stiffness and layout parameters. The interaction among gears, shafts and sliding bearings in the system was studied, and the coupling problem of nonlinear oil film force and nonlinear gear meshing force was discussed. Considering the time-varying meshing stiffness, nonlinear bearing force and gear eccentricity, Liang and Gao established a 16 degree of freedom nonlinear dynamic model of gear rotor rolling bearing transmission system with bending torsion coupling by using lumped parameter method. The coupling relationship between bearing vibration and gear vibration was studied by analyzing the influence of gear eccentricity and rotational speed on the system. Bai et al. Established a dynamic model of gear rotor bearing coupling system considering bearing surface ripple defects. The influence of bearing clearance, time-varying gear transmission error excitation and rotor flexibility was considered in the model. The effects of different rotating speeds, the number and amplitude of bearing waviness on the dynamic characteristics of the system were studied.