As the most widely used power and motion transmission device of mechanical equipment, the mechanical behavior and working performance of gear transmission system have an important impact on the whole mechanical equipment. With the continuous development and cross penetration of basic and cutting-edge disciplines, gear transmission system dynamics has made considerable progress. At present, a complete theoretical system has been formed. However, there are still some deficiencies, especially in the fault identification and diagnosis of gear transmission system.
At present, there are a lot of research results on the vibration characteristics of gear failure and rolling bearing fault, but these studies mainly study the impact of single fault on the vibration response of gear transmission system dynamic model, and judge the operation status of key components of gear transmission system. Due to the complex structure of gear transmission system, there are many contact interfaces, and the cracks, wear and spalling of its core parts often occur at the same time. The vibration signal frequency of key components such as gear pair and supporting rolling bearing is mixed. This complex vibration signal frequency undoubtedly brings more difficulties to the accurate identification of gear transmission system fault. Therefore, it is urgently needed The dynamic model of compound fault of gear transmission system is established, and the vibration response characteristics of compound fault are analyzed, which provides a theoretical basis for accurate identification and diagnosis of gear transmission system fault.
Due to the harsh working environment of the gearbox, the key parts of the gear transmission system are often damaged by different types, which leads to the failure of the gear transmission system and seriously affects the safety and stability of mechanical equipment. The structure of gear transmission system is complex, and there are many contact surfaces. Therefore, the gear transmission system often has multiple component faults at the same time, and the vibration signal frequency is complex, which brings some difficulties to the fault diagnosis and identification of gearbox. Aiming at this problem, combined with the dynamic model of gear pair and rolling bearing, a 36 DOF composite fault model of gear rolling bearing system is established. The influence of typical faults such as root crack and bearing local fault on vibration characteristics of gear transmission system is deeply analyzed, so as to provide theoretical basis for accurate identification and diagnosis of gearbox fault.