The Manufacture Faults Diagnosis And Software Development For Aerospace Bearings Based On Friction Torque

Gyroscope frame-sensitive bearing is one of the highest performance requirements of friction torque in aerospace bearings, whose value and stability of the friction torque often influence the accuracy and stability of gyroscope instruments, peak values and blocking phenomena of friction torque are not allowed in the process of usage. As far as aerospace bearings concerned, roundness and roughness of the ring and the surface scratches are the important factors which caused peak values and waveniss of friction torque, so monitoring and diagnosising these defectful bearings which are contributed by those factors are necessary, in order to guarantee the quality of bearings, and to reduce economic loss of crucial application, and to offer a theory foundation for improving sensitive bearings.In this paper, gyroscope frame-sensitive bearings were researched, manufacture quality (roundness, roughness of ring) which impact the friction torque of gyroscope frame-sensitive bearings were studied. Test datas were collected from the low speed dynamic friction torque test instrument, the diagnostic features of vibration signals were getted, friction torque signals of bearings were analyzed and discussed by the use of statistics, frequency-domain analysis and wavelet transform means and so on. Several effective time-domain parameters and frequency-domain characteristic parameters were obtained, so characteristic parameters were provided for these two bearings. At the same time roundness and characteristic frequency of surface scratches were derived. According to the characteristic parameters which have been derived, low-speed torque analysis software was developed and the software was carried out by experiments.Because there are many factors affect the friction torque, the changes of friction torque of sensitive bearings are very random. The research of friction torque is very complex and difficult. This paper has made a preliminary exploration for the study of diagnosis of aerospace bearings based on friction torque and to lay the foundation for the deeper research.